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File: option.php

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File: option.php
Role: Example script
Content type: text/plain
Description: Example script
Class: Custom Wordpress Utility Classes
Classes to speed up WordPress plugin development
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Date: 4 months ago
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<?php
//path D:\wamp64\www\turbo\wp-includes\option.php
// method to edit get_option LIMIT to 1
/**
 * Option API
 *
 * @package WordPress
 * @subpackage Option
 */

/**
 * Retrieves an option value based on an option name.
 *
 * If the option does not exist, and a default value is not provided,
 * boolean false is returned. This could be used to check whether you need
 * to initialize an option during installation of a plugin, however that
 * can be done better by using add_option() which will not overwrite
 * existing options.
 *
 * Not initializing an option and using boolean `false` as a return value
 * is a bad practice as it triggers an additional database query.
 *
 * The type of the returned value can be different from the type that was passed
 * when saving or updating the option. If the option value was serialized,
 * then it will be unserialized when it is returned. In this case the type will
 * be the same. For example, storing a non-scalar value like an array will
 * return the same array.
 *
 * In most cases non-string scalar and null values will be converted and returned
 * as string equivalents.
 *
 * Exceptions:
 * 1. When the option has not been saved in the database, the `$default` value
 *    is returned if provided. If not, boolean `false` is returned.
 * 2. When one of the Options API filters is used: {@see 'pre_option_{$option}'},
 *    {@see 'default_option_{$option}'}, or {@see 'option_{$option}'}, the returned
 *    value may not match the expected type.
 * 3. When the option has just been saved in the database, and get_option()
 *    is used right after, non-string scalar and null values are not converted to
 *    string equivalents and the original type is returned.
 *
 * Examples:
 *
 * When adding options like this: `add_option( 'my_option_name', 'value' );`
 * and then retrieving them with `get_option( 'my_option_name' );`, the returned
 * values will be:
 *
 * `false` returns `string(0) ""`
 * `true`  returns `string(1) "1"`
 * `0`     returns `string(1) "0"`
 * `1`     returns `string(1) "1"`
 * `'0'`   returns `string(1) "0"`
 * `'1'`   returns `string(1) "1"`
 * `null`  returns `string(0) ""`
 *
 * When adding options with non-scalar values like
 * `add_option( 'my_array', array( false, 'str', null ) );`, the returned value
 * will be identical to the original as it is serialized before saving
 * it in the database:
 *
 *    array(3) {
 *        [0] => bool(false)
 *        [1] => string(3) "str"
 *        [2] => NULL
 *    }
 *
 * @since 1.5.0
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param string $option  Name of the option to retrieve. Expected to not be SQL-escaped.
 * @param mixed  $default Optional. Default value to return if the option does not exist.
 * @return mixed Value of the option. A value of any type may be returned, including
 *               scalar (string, boolean, float, integer), null, array, object.
 *               Scalar and null values will be returned as strings as long as they originate
 *               from a database stored option value. If there is no option in the database,
 *               boolean `false` is returned.
 */
function get_option($option, $default = false)
{
	global $wpdb;

	if (is_scalar($option)) {
		$option = trim($option);
	}

	if (empty($option)) {
		return false;
	}

	/*
	 * Until a proper _deprecated_option() function can be introduced,
	 * redirect requests to deprecated keys to the new, correct ones.
	 */
	$deprecated_keys = array(
		'blacklist_keys'    => 'disallowed_keys',
		'comment_whitelist' => 'comment_previously_approved',
	);

	if (!wp_installing() && isset($deprecated_keys[$option])) {
		_deprecated_argument(
			__FUNCTION__,
			'5.5.0',
			sprintf(
				/* translators: 1: Deprecated option key, 2: New option key. */
				__('The "%1$s" option key has been renamed to "%2$s".'),
				$option,
				$deprecated_keys[$option]
			)
		);
		return get_option($deprecated_keys[$option], $default);
	}

	/**
	 * Filters the value of an existing option before it is retrieved.
	 *
	 * The dynamic portion of the hook name, `$option`, refers to the option name.
	 *
	 * Returning a truthy value from the filter will effectively short-circuit retrieval
	 * and return the passed value instead.
	 *
	 * @since 1.5.0
	 * @since 4.4.0 The `$option` parameter was added.
	 * @since 4.9.0 The `$default` parameter was added.
	 *
	 * @param mixed  $pre_option The value to return instead of the option value. This differs
	 *                           from `$default`, which is used as the fallback value in the event
	 *                           the option doesn't exist elsewhere in get_option().
	 *                           Default false (to skip past the short-circuit).
	 * @param string $option     Option name.
	 * @param mixed  $default    The fallback value to return if the option does not exist.
	 *                           Default false.
	 */
	$pre = apply_filters("pre_option_{$option}", false, $option, $default);

	if (false !== $pre) {
		return $pre;
	}

	if (defined('WP_SETUP_CONFIG')) {
		return false;
	}

	// Distinguish between `false` as a default, and not passing one.
	$passed_default = func_num_args() > 1;

	if (!wp_installing()) {
		// Prevent non-existent options from triggering multiple queries.
		$notoptions = wp_cache_get('notoptions', 'options');

		if (isset($notoptions[$option])) {
			/**
			 * Filters the default value for an option.
			 *
			 * The dynamic portion of the hook name, `$option`, refers to the option name.
			 *
			 * @since 3.4.0
			 * @since 4.4.0 The `$option` parameter was added.
			 * @since 4.7.0 The `$passed_default` parameter was added to distinguish between a `false` value and the default parameter value.
			 *
			 * @param mixed  $default The default value to return if the option does not exist
			 *                        in the database.
			 * @param string $option  Option name.
			 * @param bool   $passed_default Was `get_option()` passed a default value?
			 */
			return apply_filters("default_option_{$option}", $default, $option, $passed_default);
		}

		$alloptions = wp_load_alloptions();

		if (isset($alloptions[$option])) {
			$value = $alloptions[$option];
		} else {
			$value = wp_cache_get($option, 'options');

			if (false === $value) {
				$row = $wpdb->get_row($wpdb->prepare("SELECT option_value FROM $wpdb->options WHERE option_name = %s LIMIT 1", $option));

				// Has to be get_row() instead of get_var() because of funkiness with 0, false, null values.
				if (is_object($row)) {
					$value = $row->option_value;
					wp_cache_add($option, $value, 'options');
				} else { // Option does not exist, so we must cache its non-existence.
					if (!is_array($notoptions)) {
						$notoptions = array();
					}

					$notoptions[$option] = true;
					wp_cache_set('notoptions', $notoptions, 'options');

					/** This filter is documented in wp-includes/option.php */
					return apply_filters("default_option_{$option}", $default, $option, $passed_default);
				}
			}
		}
	} else {
		$suppress = $wpdb->suppress_errors();
		$row      = $wpdb->get_row($wpdb->prepare("SELECT option_value FROM $wpdb->options WHERE option_name = %s LIMIT 1", $option));
		$wpdb->suppress_errors($suppress);

		if (is_object($row)) {
			$value = $row->option_value;
		} else {
			/** This filter is documented in wp-includes/option.php */
			return apply_filters("default_option_{$option}", $default, $option, $passed_default);
		}
	}

	// If home is not set, use siteurl.
	if ('home' === $option && '' === $value) {
		return get_option('siteurl');
	}

	if (in_array($option, array('siteurl', 'home', 'category_base', 'tag_base'), true)) {
		$value = untrailingslashit($value);
	}

	/**
	 * Filters the value of an existing option.
	 *
	 * The dynamic portion of the hook name, `$option`, refers to the option name.
	 *
	 * @since 1.5.0 As 'option_' . $setting
	 * @since 3.0.0
	 * @since 4.4.0 The `$option` parameter was added.
	 *
	 * @param mixed  $value  Value of the option. If stored serialized, it will be
	 *                       unserialized prior to being returned.
	 * @param string $option Option name.
	 */
	return apply_filters("option_{$option}", maybe_unserialize($value), $option);
}

/**
 * Protects WordPress special option from being modified.
 *
 * Will die if $option is in protected list. Protected options are 'alloptions'
 * and 'notoptions' options.
 *
 * @since 2.2.0
 *
 * @param string $option Option name.
 */
function wp_protect_special_option($option)
{
	if ('alloptions' === $option || 'notoptions' === $option) {
		wp_die(
			sprintf(
				/* translators: %s: Option name. */
				__('%s is a protected WP option and may not be modified'),
				esc_html($option)
			)
		);
	}
}

/**
 * Prints option value after sanitizing for forms.
 *
 * @since 1.5.0
 *
 * @param string $option Option name.
 */
function form_option($option)
{
	echo esc_attr(get_option($option));
}

/**
 * Loads and caches all autoloaded options, if available or all options.
 *
 * @since 2.2.0
 * @since 5.3.1 The `$force_cache` parameter was added.
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param bool $force_cache Optional. Whether to force an update of the local cache
 *                          from the persistent cache. Default false.
 * @return array List of all options.
 */
function wp_load_alloptions($force_cache = false)
{
	global $wpdb;

	if (!wp_installing() || !is_multisite()) {
		$alloptions = wp_cache_get('alloptions', 'options', $force_cache);
	} else {
		$alloptions = false;
	}

	if (!$alloptions) {
		$suppress      = $wpdb->suppress_errors();
		$alloptions_db = $wpdb->get_results("SELECT option_name, option_value FROM $wpdb->options WHERE autoload = 'yes' LIMIT 10");
		if (!$alloptions_db) {
			$alloptions_db = $wpdb->get_results("SELECT option_name, option_value FROM $wpdb->options");
		}
		$wpdb->suppress_errors($suppress);

		$alloptions = array();
		foreach ((array) $alloptions_db as $o) {
			$alloptions[$o->option_name] = $o->option_value;
		}

		if (!wp_installing() || !is_multisite()) {
			/**
			 * Filters all options before caching them.
			 *
			 * @since 4.9.0
			 *
			 * @param array $alloptions Array with all options.
			 */
			$alloptions = apply_filters('pre_cache_alloptions', $alloptions);

			wp_cache_add('alloptions', $alloptions, 'options');
		}
	}

	/**
	 * Filters all options after retrieving them.
	 *
	 * @since 4.9.0
	 *
	 * @param array $alloptions Array with all options.
	 */
	return apply_filters('alloptions', $alloptions);
}

/**
 * Loads and caches certain often requested site options if is_multisite() and a persistent cache is not being used.
 *
 * @since 3.0.0
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param int $network_id Optional site ID for which to query the options. Defaults to the current site.
 */
function wp_load_core_site_options($network_id = null)
{
	global $wpdb;

	if (!is_multisite() || wp_using_ext_object_cache() || wp_installing()) {
		return;
	}

	if (empty($network_id)) {
		$network_id = get_current_network_id();
	}

	$core_options = array('site_name', 'siteurl', 'active_sitewide_plugins', '_site_transient_timeout_theme_roots', '_site_transient_theme_roots', 'site_admins', 'can_compress_scripts', 'global_terms_enabled', 'ms_files_rewriting');

	$core_options_in = "'" . implode("', '", $core_options) . "'";
	$options         = $wpdb->get_results($wpdb->prepare("SELECT meta_key, meta_value FROM $wpdb->sitemeta WHERE meta_key IN ($core_options_in) AND site_id = %d", $network_id));

	foreach ($options as $option) {
		$key                = $option->meta_key;
		$cache_key          = "{$network_id}:$key";
		$option->meta_value = maybe_unserialize($option->meta_value);

		wp_cache_set($cache_key, $option->meta_value, 'site-options');
	}
}

/**
 * Updates the value of an option that was already added.
 *
 * You do not need to serialize values. If the value needs to be serialized,
 * then it will be serialized before it is inserted into the database.
 * Remember, resources cannot be serialized or added as an option.
 *
 * If the option does not exist, it will be created.

 * This function is designed to work with or without a logged-in user. In terms of security,
 * plugin developers should check the current user's capabilities before updating any options.
 *
 * @since 1.0.0
 * @since 4.2.0 The `$autoload` parameter was added.
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param string      $option   Name of the option to update. Expected to not be SQL-escaped.
 * @param mixed       $value    Option value. Must be serializable if non-scalar. Expected to not be SQL-escaped.
 * @param string|bool $autoload Optional. Whether to load the option when WordPress starts up. For existing options,
 *                              `$autoload` can only be updated using `update_option()` if `$value` is also changed.
 *                              Accepts 'yes'|true to enable or 'no'|false to disable. For non-existent options,
 *                              the default value is 'yes'. Default null.
 * @return bool True if the value was updated, false otherwise.
 */
function update_option($option, $value, $autoload = null)
{
	global $wpdb;

	if (is_scalar($option)) {
		$option = trim($option);
	}

	if (empty($option)) {
		return false;
	}

	/*
	 * Until a proper _deprecated_option() function can be introduced,
	 * redirect requests to deprecated keys to the new, correct ones.
	 */
	$deprecated_keys = array(
		'blacklist_keys'    => 'disallowed_keys',
		'comment_whitelist' => 'comment_previously_approved',
	);

	if (!wp_installing() && isset($deprecated_keys[$option])) {
		_deprecated_argument(
			__FUNCTION__,
			'5.5.0',
			sprintf(
				/* translators: 1: Deprecated option key, 2: New option key. */
				__('The "%1$s" option key has been renamed to "%2$s".'),
				$option,
				$deprecated_keys[$option]
			)
		);
		return update_option($deprecated_keys[$option], $value, $autoload);
	}

	wp_protect_special_option($option);

	if (is_object($value)) {
		$value = clone $value;
	}

	$value     = sanitize_option($option, $value);
	$old_value = get_option($option);

	/**
	 * Filters a specific option before its value is (maybe) serialized and updated.
	 *
	 * The dynamic portion of the hook name, `$option`, refers to the option name.
	 *
	 * @since 2.6.0
	 * @since 4.4.0 The `$option` parameter was added.
	 *
	 * @param mixed  $value     The new, unserialized option value.
	 * @param mixed  $old_value The old option value.
	 * @param string $option    Option name.
	 */
	$value = apply_filters("pre_update_option_{$option}", $value, $old_value, $option);

	/**
	 * Filters an option before its value is (maybe) serialized and updated.
	 *
	 * @since 3.9.0
	 *
	 * @param mixed  $value     The new, unserialized option value.
	 * @param string $option    Name of the option.
	 * @param mixed  $old_value The old option value.
	 */
	$value = apply_filters('pre_update_option', $value, $option, $old_value);

	/*
	 * If the new and old values are the same, no need to update.
	 *
	 * Unserialized values will be adequate in most cases. If the unserialized
	 * data differs, the (maybe) serialized data is checked to avoid
	 * unnecessary database calls for otherwise identical object instances.
	 *
	 * See https://core.trac.wordpress.org/ticket/38903
	 */
	if ($value === $old_value || maybe_serialize($value) === maybe_serialize($old_value)) {
		return false;
	}

	/** This filter is documented in wp-includes/option.php */
	if (apply_filters("default_option_{$option}", false, $option, false) === $old_value) {
		// Default setting for new options is 'yes'.
		if (null === $autoload) {
			$autoload = 'yes';
		}

		return add_option($option, $value, '', $autoload);
	}

	$serialized_value = maybe_serialize($value);

	/**
	 * Fires immediately before an option value is updated.
	 *
	 * @since 2.9.0
	 *
	 * @param string $option    Name of the option to update.
	 * @param mixed  $old_value The old option value.
	 * @param mixed  $value     The new option value.
	 */
	do_action('update_option', $option, $old_value, $value);

	$update_args = array(
		'option_value' => $serialized_value,
	);

	if (null !== $autoload) {
		$update_args['autoload'] = ('no' === $autoload || false === $autoload) ? 'no' : 'yes';
	}

	$result = $wpdb->update($wpdb->options, $update_args, array('option_name' => $option));
	if (!$result) {
		return false;
	}

	$notoptions = wp_cache_get('notoptions', 'options');

	if (is_array($notoptions) && isset($notoptions[$option])) {
		unset($notoptions[$option]);
		wp_cache_set('notoptions', $notoptions, 'options');
	}

	if (!wp_installing()) {
		$alloptions = wp_load_alloptions(true);
		if (isset($alloptions[$option])) {
			$alloptions[$option] = $serialized_value;
			wp_cache_set('alloptions', $alloptions, 'options');
		} else {
			wp_cache_set($option, $serialized_value, 'options');
		}
	}

	/**
	 * Fires after the value of a specific option has been successfully updated.
	 *
	 * The dynamic portion of the hook name, `$option`, refers to the option name.
	 *
	 * @since 2.0.1
	 * @since 4.4.0 The `$option` parameter was added.
	 *
	 * @param mixed  $old_value The old option value.
	 * @param mixed  $value     The new option value.
	 * @param string $option    Option name.
	 */
	do_action("update_option_{$option}", $old_value, $value, $option);

	/**
	 * Fires after the value of an option has been successfully updated.
	 *
	 * @since 2.9.0
	 *
	 * @param string $option    Name of the updated option.
	 * @param mixed  $old_value The old option value.
	 * @param mixed  $value     The new option value.
	 */
	do_action('updated_option', $option, $old_value, $value);

	return true;
}

/**
 * Adds a new option.
 *
 * You do not need to serialize values. If the value needs to be serialized,
 * then it will be serialized before it is inserted into the database.
 * Remember, resources cannot be serialized or added as an option.
 *
 * You can create options without values and then update the values later.
 * Existing options will not be updated and checks are performed to ensure that you
 * aren't adding a protected WordPress option. Care should be taken to not name
 * options the same as the ones which are protected.
 *
 * @since 1.0.0
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param string      $option     Name of the option to add. Expected to not be SQL-escaped.
 * @param mixed       $value      Optional. Option value. Must be serializable if non-scalar.
 *                                Expected to not be SQL-escaped.
 * @param string      $deprecated Optional. Description. Not used anymore.
 * @param string|bool $autoload   Optional. Whether to load the option when WordPress starts up.
 *                                Default is enabled. Accepts 'no' to disable for legacy reasons.
 * @return bool True if the option was added, false otherwise.
 */
function add_option($option, $value = '', $deprecated = '', $autoload = 'yes')
{
	global $wpdb;

	if (!empty($deprecated)) {
		_deprecated_argument(__FUNCTION__, '2.3.0');
	}

	if (is_scalar($option)) {
		$option = trim($option);
	}

	if (empty($option)) {
		return false;
	}

	/*
	 * Until a proper _deprecated_option() function can be introduced,
	 * redirect requests to deprecated keys to the new, correct ones.
	 */
	$deprecated_keys = array(
		'blacklist_keys'    => 'disallowed_keys',
		'comment_whitelist' => 'comment_previously_approved',
	);

	if (!wp_installing() && isset($deprecated_keys[$option])) {
		_deprecated_argument(
			__FUNCTION__,
			'5.5.0',
			sprintf(
				/* translators: 1: Deprecated option key, 2: New option key. */
				__('The "%1$s" option key has been renamed to "%2$s".'),
				$option,
				$deprecated_keys[$option]
			)
		);
		return add_option($deprecated_keys[$option], $value, $deprecated, $autoload);
	}

	wp_protect_special_option($option);

	if (is_object($value)) {
		$value = clone $value;
	}

	$value = sanitize_option($option, $value);

	// Make sure the option doesn't already exist.
	// We can check the 'notoptions' cache before we ask for a DB query.
	$notoptions = wp_cache_get('notoptions', 'options');

	if (!is_array($notoptions) || !isset($notoptions[$option])) {
		/** This filter is documented in wp-includes/option.php */
		if (apply_filters("default_option_{$option}", false, $option, false) !== get_option($option)) {
			return false;
		}
	}

	$serialized_value = maybe_serialize($value);
	$autoload         = ('no' === $autoload || false === $autoload) ? 'no' : 'yes';

	/**
	 * Fires before an option is added.
	 *
	 * @since 2.9.0
	 *
	 * @param string $option Name of the option to add.
	 * @param mixed  $value  Value of the option.
	 */
	do_action('add_option', $option, $value);

	$result = $wpdb->query($wpdb->prepare("INSERT INTO `$wpdb->options` (`option_name`, `option_value`, `autoload`) VALUES (%s, %s, %s) ON DUPLICATE KEY UPDATE `option_name` = VALUES(`option_name`), `option_value` = VALUES(`option_value`), `autoload` = VALUES(`autoload`)", $option, $serialized_value, $autoload));
	if (!$result) {
		return false;
	}

	if (!wp_installing()) {
		if ('yes' === $autoload) {
			$alloptions            = wp_load_alloptions(true);
			$alloptions[$option] = $serialized_value;
			wp_cache_set('alloptions', $alloptions, 'options');
		} else {
			wp_cache_set($option, $serialized_value, 'options');
		}
	}

	// This option exists now.
	$notoptions = wp_cache_get('notoptions', 'options'); // Yes, again... we need it to be fresh.

	if (is_array($notoptions) && isset($notoptions[$option])) {
		unset($notoptions[$option]);
		wp_cache_set('notoptions', $notoptions, 'options');
	}

	/**
	 * Fires after a specific option has been added.
	 *
	 * The dynamic portion of the hook name, `$option`, refers to the option name.
	 *
	 * @since 2.5.0 As "add_option_{$name}"
	 * @since 3.0.0
	 *
	 * @param string $option Name of the option to add.
	 * @param mixed  $value  Value of the option.
	 */
	do_action("add_option_{$option}", $option, $value);

	/**
	 * Fires after an option has been added.
	 *
	 * @since 2.9.0
	 *
	 * @param string $option Name of the added option.
	 * @param mixed  $value  Value of the option.
	 */
	do_action('added_option', $option, $value);

	return true;
}

/**
 * Removes option by name. Prevents removal of protected WordPress options.
 *
 * @since 1.2.0
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param string $option Name of the option to delete. Expected to not be SQL-escaped.
 * @return bool True if the option was deleted, false otherwise.
 */
function delete_option($option)
{
	global $wpdb;

	if (is_scalar($option)) {
		$option = trim($option);
	}

	if (empty($option)) {
		return false;
	}

	wp_protect_special_option($option);

	// Get the ID, if no ID then return.
	$row = $wpdb->get_row($wpdb->prepare("SELECT autoload FROM $wpdb->options WHERE option_name = %s", $option));
	if (is_null($row)) {
		return false;
	}

	/**
	 * Fires immediately before an option is deleted.
	 *
	 * @since 2.9.0
	 *
	 * @param string $option Name of the option to delete.
	 */
	do_action('delete_option', $option);

	$result = $wpdb->delete($wpdb->options, array('option_name' => $option));

	if (!wp_installing()) {
		if ('yes' === $row->autoload) {
			$alloptions = wp_load_alloptions(true);
			if (is_array($alloptions) && isset($alloptions[$option])) {
				unset($alloptions[$option]);
				wp_cache_set('alloptions', $alloptions, 'options');
			}
		} else {
			wp_cache_delete($option, 'options');
		}
	}

	if ($result) {

		/**
		 * Fires after a specific option has been deleted.
		 *
		 * The dynamic portion of the hook name, `$option`, refers to the option name.
		 *
		 * @since 3.0.0
		 *
		 * @param string $option Name of the deleted option.
		 */
		do_action("delete_option_{$option}", $option);

		/**
		 * Fires after an option has been deleted.
		 *
		 * @since 2.9.0
		 *
		 * @param string $option Name of the deleted option.
		 */
		do_action('deleted_option', $option);

		return true;
	}

	return false;
}

/**
 * Deletes a transient.
 *
 * @since 2.8.0
 *
 * @param string $transient Transient name. Expected to not be SQL-escaped.
 * @return bool True if the transient was deleted, false otherwise.
 */
function delete_transient($transient)
{

	/**
	 * Fires immediately before a specific transient is deleted.
	 *
	 * The dynamic portion of the hook name, `$transient`, refers to the transient name.
	 *
	 * @since 3.0.0
	 *
	 * @param string $transient Transient name.
	 */
	do_action("delete_transient_{$transient}", $transient);

	if (wp_using_ext_object_cache() || wp_installing()) {
		$result = wp_cache_delete($transient, 'transient');
	} else {
		$option_timeout = '_transient_timeout_' . $transient;
		$option         = '_transient_' . $transient;
		$result         = delete_option($option);

		if ($result) {
			delete_option($option_timeout);
		}
	}

	if ($result) {

		/**
		 * Fires after a transient is deleted.
		 *
		 * @since 3.0.0
		 *
		 * @param string $transient Deleted transient name.
		 */
		do_action('deleted_transient', $transient);
	}

	return $result;
}

/**
 * Retrieves the value of a transient.
 *
 * If the transient does not exist, does not have a value, or has expired,
 * then the return value will be false.
 *
 * @since 2.8.0
 *
 * @param string $transient Transient name. Expected to not be SQL-escaped.
 * @return mixed Value of transient.
 */
function get_transient($transient)
{

	/**
	 * Filters the value of an existing transient before it is retrieved.
	 *
	 * The dynamic portion of the hook name, `$transient`, refers to the transient name.
	 *
	 * Returning a truthy value from the filter will effectively short-circuit retrieval
	 * and return the passed value instead.
	 *
	 * @since 2.8.0
	 * @since 4.4.0 The `$transient` parameter was added
	 *
	 * @param mixed  $pre_transient The default value to return if the transient does not exist.
	 *                              Any value other than false will short-circuit the retrieval
	 *                              of the transient, and return that value.
	 * @param string $transient     Transient name.
	 */
	$pre = apply_filters("pre_transient_{$transient}", false, $transient);

	if (false !== $pre) {
		return $pre;
	}

	if (wp_using_ext_object_cache() || wp_installing()) {
		$value = wp_cache_get($transient, 'transient');
	} else {
		$transient_option = '_transient_' . $transient;
		if (!wp_installing()) {
			// If option is not in alloptions, it is not autoloaded and thus has a timeout.
			$alloptions = wp_load_alloptions();
			if (!isset($alloptions[$transient_option])) {
				$transient_timeout = '_transient_timeout_' . $transient;
				$timeout           = get_option($transient_timeout);
				if (false !== $timeout && $timeout < time()) {
					delete_option($transient_option);
					delete_option($transient_timeout);
					$value = false;
				}
			}
		}

		if (!isset($value)) {
			$value = get_option($transient_option);
		}
	}

	/**
	 * Filters an existing transient's value.
	 *
	 * The dynamic portion of the hook name, `$transient`, refers to the transient name.
	 *
	 * @since 2.8.0
	 * @since 4.4.0 The `$transient` parameter was added
	 *
	 * @param mixed  $value     Value of transient.
	 * @param string $transient Transient name.
	 */
	return apply_filters("transient_{$transient}", $value, $transient);
}

/**
 * Sets/updates the value of a transient.
 *
 * You do not need to serialize values. If the value needs to be serialized,
 * then it will be serialized before it is set.
 *
 * @since 2.8.0
 *
 * @param string $transient  Transient name. Expected to not be SQL-escaped.
 *                           Must be 172 characters or fewer in length.
 * @param mixed  $value      Transient value. Must be serializable if non-scalar.
 *                           Expected to not be SQL-escaped.
 * @param int    $expiration Optional. Time until expiration in seconds. Default 0 (no expiration).
 * @return bool True if the value was set, false otherwise.
 */
function set_transient($transient, $value, $expiration = 0)
{

	$expiration = (int) $expiration;

	/**
	 * Filters a specific transient before its value is set.
	 *
	 * The dynamic portion of the hook name, `$transient`, refers to the transient name.
	 *
	 * @since 3.0.0
	 * @since 4.2.0 The `$expiration` parameter was added.
	 * @since 4.4.0 The `$transient` parameter was added.
	 *
	 * @param mixed  $value      New value of transient.
	 * @param int    $expiration Time until expiration in seconds.
	 * @param string $transient  Transient name.
	 */
	$value = apply_filters("pre_set_transient_{$transient}", $value, $expiration, $transient);

	/**
	 * Filters the expiration for a transient before its value is set.
	 *
	 * The dynamic portion of the hook name, `$transient`, refers to the transient name.
	 *
	 * @since 4.4.0
	 *
	 * @param int    $expiration Time until expiration in seconds. Use 0 for no expiration.
	 * @param mixed  $value      New value of transient.
	 * @param string $transient  Transient name.
	 */
	$expiration = apply_filters("expiration_of_transient_{$transient}", $expiration, $value, $transient);

	if (wp_using_ext_object_cache() || wp_installing()) {
		$result = wp_cache_set($transient, $value, 'transient', $expiration);
	} else {
		$transient_timeout = '_transient_timeout_' . $transient;
		$transient_option  = '_transient_' . $transient;

		if (false === get_option($transient_option)) {
			$autoload = 'yes';
			if ($expiration) {
				$autoload = 'no';
				add_option($transient_timeout, time() + $expiration, '', 'no');
			}
			$result = add_option($transient_option, $value, '', $autoload);
		} else {
			// If expiration is requested, but the transient has no timeout option,
			// delete, then re-create transient rather than update.
			$update = true;

			if ($expiration) {
				if (false === get_option($transient_timeout)) {
					delete_option($transient_option);
					add_option($transient_timeout, time() + $expiration, '', 'no');
					$result = add_option($transient_option, $value, '', 'no');
					$update = false;
				} else {
					update_option($transient_timeout, time() + $expiration);
				}
			}

			if ($update) {
				$result = update_option($transient_option, $value);
			}
		}
	}

	if ($result) {

		/**
		 * Fires after the value for a specific transient has been set.
		 *
		 * The dynamic portion of the hook name, `$transient`, refers to the transient name.
		 *
		 * @since 3.0.0
		 * @since 3.6.0 The `$value` and `$expiration` parameters were added.
		 * @since 4.4.0 The `$transient` parameter was added.
		 *
		 * @param mixed  $value      Transient value.
		 * @param int    $expiration Time until expiration in seconds.
		 * @param string $transient  The name of the transient.
		 */
		do_action("set_transient_{$transient}", $value, $expiration, $transient);

		/**
		 * Fires after the value for a transient has been set.
		 *
		 * @since 3.0.0
		 * @since 3.6.0 The `$value` and `$expiration` parameters were added.
		 *
		 * @param string $transient  The name of the transient.
		 * @param mixed  $value      Transient value.
		 * @param int    $expiration Time until expiration in seconds.
		 */
		do_action('setted_transient', $transient, $value, $expiration);
	}

	return $result;
}

/**
 * Deletes all expired transients.
 *
 * The multi-table delete syntax is used to delete the transient record
 * from table a, and the corresponding transient_timeout record from table b.
 *
 * @since 4.9.0
 *
 * @param bool $force_db Optional. Force cleanup to run against the database even when an external object cache is used.
 */
function delete_expired_transients($force_db = false)
{
	global $wpdb;

	if (!$force_db && wp_using_ext_object_cache()) {
		return;
	}

	$wpdb->query(
		$wpdb->prepare(
			"DELETE a, b FROM {$wpdb->options} a, {$wpdb->options} b
			WHERE a.option_name LIKE %s
			AND a.option_name NOT LIKE %s
			AND b.option_name = CONCAT( '_transient_timeout_', SUBSTRING( a.option_name, 12 ) )
			AND b.option_value < %d",
			$wpdb->esc_like('_transient_') . '%',
			$wpdb->esc_like('_transient_timeout_') . '%',
			time()
		)
	);

	if (!is_multisite()) {
		// Single site stores site transients in the options table.
		$wpdb->query(
			$wpdb->prepare(
				"DELETE a, b FROM {$wpdb->options} a, {$wpdb->options} b
				WHERE a.option_name LIKE %s
				AND a.option_name NOT LIKE %s
				AND b.option_name = CONCAT( '_site_transient_timeout_', SUBSTRING( a.option_name, 17 ) )
				AND b.option_value < %d",
				$wpdb->esc_like('_site_transient_') . '%',
				$wpdb->esc_like('_site_transient_timeout_') . '%',
				time()
			)
		);
	} elseif (is_multisite() && is_main_site() && is_main_network()) {
		// Multisite stores site transients in the sitemeta table.
		$wpdb->query(
			$wpdb->prepare(
				"DELETE a, b FROM {$wpdb->sitemeta} a, {$wpdb->sitemeta} b
				WHERE a.meta_key LIKE %s
				AND a.meta_key NOT LIKE %s
				AND b.meta_key = CONCAT( '_site_transient_timeout_', SUBSTRING( a.meta_key, 17 ) )
				AND b.meta_value < %d",
				$wpdb->esc_like('_site_transient_') . '%',
				$wpdb->esc_like('_site_transient_timeout_') . '%',
				time()
			)
		);
	}
}

/**
 * Saves and restores user interface settings stored in a cookie.
 *
 * Checks if the current user-settings cookie is updated and stores it. When no
 * cookie exists (different browser used), adds the last saved cookie restoring
 * the settings.
 *
 * @since 2.7.0
 */
function wp_user_settings()
{

	if (!is_admin() || wp_doing_ajax()) {
		return;
	}

	$user_id = get_current_user_id();
	if (!$user_id) {
		return;
	}

	if (!is_user_member_of_blog()) {
		return;
	}

	$settings = (string) get_user_option('user-settings', $user_id);

	if (isset($_COOKIE['wp-settings-' . $user_id])) {
		$cookie = preg_replace('/[^A-Za-z0-9=&_]/', '', $_COOKIE['wp-settings-' . $user_id]);

		// No change or both empty.
		if ($cookie == $settings) {
			return;
		}

		$last_saved = (int) get_user_option('user-settings-time', $user_id);
		$current    = isset($_COOKIE['wp-settings-time-' . $user_id]) ? preg_replace('/[^0-9]/', '', $_COOKIE['wp-settings-time-' . $user_id]) : 0;

		// The cookie is newer than the saved value. Update the user_option and leave the cookie as-is.
		if ($current > $last_saved) {
			update_user_option($user_id, 'user-settings', $cookie, false);
			update_user_option($user_id, 'user-settings-time', time() - 5, false);
			return;
		}
	}

	// The cookie is not set in the current browser or the saved value is newer.
	$secure = ('https' === parse_url(admin_url(), PHP_URL_SCHEME));
	setcookie('wp-settings-' . $user_id, $settings, time() + YEAR_IN_SECONDS, SITECOOKIEPATH, null, $secure);
	setcookie('wp-settings-time-' . $user_id, time(), time() + YEAR_IN_SECONDS, SITECOOKIEPATH, null, $secure);
	$_COOKIE['wp-settings-' . $user_id] = $settings;
}

/**
 * Retrieves user interface setting value based on setting name.
 *
 * @since 2.7.0
 *
 * @param string       $name    The name of the setting.
 * @param string|false $default Optional. Default value to return when $name is not set. Default false.
 * @return mixed The last saved user setting or the default value/false if it doesn't exist.
 */
function get_user_setting($name, $default = false)
{
	$all_user_settings = get_all_user_settings();

	return isset($all_user_settings[$name]) ? $all_user_settings[$name] : $default;
}

/**
 * Adds or updates user interface setting.
 *
 * Both $name and $value can contain only ASCII letters, numbers, hyphens, and underscores.
 *
 * This function has to be used before any output has started as it calls setcookie().
 *
 * @since 2.8.0
 *
 * @param string $name  The name of the setting.
 * @param string $value The value for the setting.
 * @return bool|null True if set successfully, false otherwise.
 *                   Null if the current user is not a member of the site.
 */
function set_user_setting($name, $value)
{
	if (headers_sent()) {
		return false;
	}

	$all_user_settings          = get_all_user_settings();
	$all_user_settings[$name] = $value;

	return wp_set_all_user_settings($all_user_settings);
}

/**
 * Deletes user interface settings.
 *
 * Deleting settings would reset them to the defaults.
 *
 * This function has to be used before any output has started as it calls setcookie().
 *
 * @since 2.7.0
 *
 * @param string $names The name or array of names of the setting to be deleted.
 * @return bool|null True if deleted successfully, false otherwise.
 *                   Null if the current user is not a member of the site.
 */
function delete_user_setting($names)
{
	if (headers_sent()) {
		return false;
	}

	$all_user_settings = get_all_user_settings();
	$names             = (array) $names;
	$deleted           = false;

	foreach ($names as $name) {
		if (isset($all_user_settings[$name])) {
			unset($all_user_settings[$name]);
			$deleted = true;
		}
	}

	if ($deleted) {
		return wp_set_all_user_settings($all_user_settings);
	}

	return false;
}

/**
 * Retrieves all user interface settings.
 *
 * @since 2.7.0
 *
 * @global array $_updated_user_settings
 *
 * @return array The last saved user settings or empty array.
 */
function get_all_user_settings()
{
	global $_updated_user_settings;

	$user_id = get_current_user_id();
	if (!$user_id) {
		return array();
	}

	if (isset($_updated_user_settings) && is_array($_updated_user_settings)) {
		return $_updated_user_settings;
	}

	$user_settings = array();

	if (isset($_COOKIE['wp-settings-' . $user_id])) {
		$cookie = preg_replace('/[^A-Za-z0-9=&_-]/', '', $_COOKIE['wp-settings-' . $user_id]);

		if (strpos($cookie, '=')) { // '=' cannot be 1st char.
			parse_str($cookie, $user_settings);
		}
	} else {
		$option = get_user_option('user-settings', $user_id);

		if ($option && is_string($option)) {
			parse_str($option, $user_settings);
		}
	}

	$_updated_user_settings = $user_settings;
	return $user_settings;
}

/**
 * Private. Sets all user interface settings.
 *
 * @since 2.8.0
 * @access private
 *
 * @global array $_updated_user_settings
 *
 * @param array $user_settings User settings.
 * @return bool|null True if set successfully, false if the current user could not be found.
 *                   Null if the current user is not a member of the site.
 */
function wp_set_all_user_settings($user_settings)
{
	global $_updated_user_settings;

	$user_id = get_current_user_id();
	if (!$user_id) {
		return false;
	}

	if (!is_user_member_of_blog()) {
		return;
	}

	$settings = '';
	foreach ($user_settings as $name => $value) {
		$_name  = preg_replace('/[^A-Za-z0-9_-]+/', '', $name);
		$_value = preg_replace('/[^A-Za-z0-9_-]+/', '', $value);

		if (!empty($_name)) {
			$settings .= $_name . '=' . $_value . '&';
		}
	}

	$settings = rtrim($settings, '&');
	parse_str($settings, $_updated_user_settings);

	update_user_option($user_id, 'user-settings', $settings, false);
	update_user_option($user_id, 'user-settings-time', time(), false);

	return true;
}

/**
 * Deletes the user settings of the current user.
 *
 * @since 2.7.0
 */
function delete_all_user_settings()
{
	$user_id = get_current_user_id();
	if (!$user_id) {
		return;
	}

	update_user_option($user_id, 'user-settings', '', false);
	setcookie('wp-settings-' . $user_id, ' ', time() - YEAR_IN_SECONDS, SITECOOKIEPATH);
}

/**
 * Retrieve an option value for the current network based on name of option.
 *
 * @since 2.8.0
 * @since 4.4.0 The `$use_cache` parameter was deprecated.
 * @since 4.4.0 Modified into wrapper for get_network_option()
 *
 * @see get_network_option()
 *
 * @param string $option     Name of the option to retrieve. Expected to not be SQL-escaped.
 * @param mixed  $default    Optional. Value to return if the option doesn't exist. Default false.
 * @param bool   $deprecated Whether to use cache. Multisite only. Always set to true.
 * @return mixed Value set for the option.
 */
function get_site_option($option, $default = false, $deprecated = true)
{
	return get_network_option(null, $option, $default);
}

/**
 * Adds a new option for the current network.
 *
 * Existing options will not be updated. Note that prior to 3.3 this wasn't the case.
 *
 * @since 2.8.0
 * @since 4.4.0 Modified into wrapper for add_network_option()
 *
 * @see add_network_option()
 *
 * @param string $option Name of the option to add. Expected to not be SQL-escaped.
 * @param mixed  $value  Option value, can be anything. Expected to not be SQL-escaped.
 * @return bool True if the option was added, false otherwise.
 */
function add_site_option($option, $value)
{
	return add_network_option(null, $option, $value);
}

/**
 * Removes a option by name for the current network.
 *
 * @since 2.8.0
 * @since 4.4.0 Modified into wrapper for delete_network_option()
 *
 * @see delete_network_option()
 *
 * @param string $option Name of the option to delete. Expected to not be SQL-escaped.
 * @return bool True if the option was deleted, false otherwise.
 */
function delete_site_option($option)
{
	return delete_network_option(null, $option);
}

/**
 * Updates the value of an option that was already added for the current network.
 *
 * @since 2.8.0
 * @since 4.4.0 Modified into wrapper for update_network_option()
 *
 * @see update_network_option()
 *
 * @param string $option Name of the option. Expected to not be SQL-escaped.
 * @param mixed  $value  Option value. Expected to not be SQL-escaped.
 * @return bool True if the value was updated, false otherwise.
 */
function update_site_option($option, $value)
{
	return update_network_option(null, $option, $value);
}

/**
 * Retrieves a network's option value based on the option name.
 *
 * @since 4.4.0
 *
 * @see get_option()
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param int    $network_id ID of the network. Can be null to default to the current network ID.
 * @param string $option     Name of the option to retrieve. Expected to not be SQL-escaped.
 * @param mixed  $default    Optional. Value to return if the option doesn't exist. Default false.
 * @return mixed Value set for the option.
 */
function get_network_option($network_id, $option, $default = false)
{
	global $wpdb;

	if ($network_id && !is_numeric($network_id)) {
		return false;
	}

	$network_id = (int) $network_id;

	// Fallback to the current network if a network ID is not specified.
	if (!$network_id) {
		$network_id = get_current_network_id();
	}

	/**
	 * Filters the value of an existing network option before it is retrieved.
	 *
	 * The dynamic portion of the hook name, `$option`, refers to the option name.
	 *
	 * Returning a truthy value from the filter will effectively short-circuit retrieval
	 * and return the passed value instead.
	 *
	 * @since 2.9.0 As 'pre_site_option_' . $key
	 * @since 3.0.0
	 * @since 4.4.0 The `$option` parameter was added.
	 * @since 4.7.0 The `$network_id` parameter was added.
	 * @since 4.9.0 The `$default` parameter was added.
	 *
	 * @param mixed  $pre_option The value to return instead of the option value. This differs
	 *                           from `$default`, which is used as the fallback value in the event
	 *                           the option doesn't exist elsewhere in get_network_option().
	 *                           Default false (to skip past the short-circuit).
	 * @param string $option     Option name.
	 * @param int    $network_id ID of the network.
	 * @param mixed  $default    The fallback value to return if the option does not exist.
	 *                           Default false.
	 */
	$pre = apply_filters("pre_site_option_{$option}", false, $option, $network_id, $default);

	if (false !== $pre) {
		return $pre;
	}

	// Prevent non-existent options from triggering multiple queries.
	$notoptions_key = "$network_id:notoptions";
	$notoptions     = wp_cache_get($notoptions_key, 'site-options');

	if (is_array($notoptions) && isset($notoptions[$option])) {

		/**
		 * Filters a specific default network option.
		 *
		 * The dynamic portion of the hook name, `$option`, refers to the option name.
		 *
		 * @since 3.4.0
		 * @since 4.4.0 The `$option` parameter was added.
		 * @since 4.7.0 The `$network_id` parameter was added.
		 *
		 * @param mixed  $default    The value to return if the site option does not exist
		 *                           in the database.
		 * @param string $option     Option name.
		 * @param int    $network_id ID of the network.
		 */
		return apply_filters("default_site_option_{$option}", $default, $option, $network_id);
	}

	if (!is_multisite()) {
		/** This filter is documented in wp-includes/option.php */
		$default = apply_filters('default_site_option_' . $option, $default, $option, $network_id);
		$value   = get_option($option, $default);
	} else {
		$cache_key = "$network_id:$option";
		$value     = wp_cache_get($cache_key, 'site-options');

		if (!isset($value) || false === $value) {
			$row = $wpdb->get_row($wpdb->prepare("SELECT meta_value FROM $wpdb->sitemeta WHERE meta_key = %s AND site_id = %d", $option, $network_id));

			// Has to be get_row() instead of get_var() because of funkiness with 0, false, null values.
			if (is_object($row)) {
				$value = $row->meta_value;
				$value = maybe_unserialize($value);
				wp_cache_set($cache_key, $value, 'site-options');
			} else {
				if (!is_array($notoptions)) {
					$notoptions = array();
				}

				$notoptions[$option] = true;
				wp_cache_set($notoptions_key, $notoptions, 'site-options');

				/** This filter is documented in wp-includes/option.php */
				$value = apply_filters('default_site_option_' . $option, $default, $option, $network_id);
			}
		}
	}

	if (!is_array($notoptions)) {
		$notoptions = array();
		wp_cache_set($notoptions_key, $notoptions, 'site-options');
	}

	/**
	 * Filters the value of an existing network option.
	 *
	 * The dynamic portion of the hook name, `$option`, refers to the option name.
	 *
	 * @since 2.9.0 As 'site_option_' . $key
	 * @since 3.0.0
	 * @since 4.4.0 The `$option` parameter was added.
	 * @since 4.7.0 The `$network_id` parameter was added.
	 *
	 * @param mixed  $value      Value of network option.
	 * @param string $option     Option name.
	 * @param int    $network_id ID of the network.
	 */
	return apply_filters("site_option_{$option}", $value, $option, $network_id);
}

/**
 * Adds a new network option.
 *
 * Existing options will not be updated.
 *
 * @since 4.4.0
 *
 * @see add_option()
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param int    $network_id ID of the network. Can be null to default to the current network ID.
 * @param string $option     Name of the option to add. Expected to not be SQL-escaped.
 * @param mixed  $value      Option value, can be anything. Expected to not be SQL-escaped.
 * @return bool True if the option was added, false otherwise.
 */
function add_network_option($network_id, $option, $value)
{
	global $wpdb;

	if ($network_id && !is_numeric($network_id)) {
		return false;
	}

	$network_id = (int) $network_id;

	// Fallback to the current network if a network ID is not specified.
	if (!$network_id) {
		$network_id = get_current_network_id();
	}

	wp_protect_special_option($option);

	/**
	 * Filters the value of a specific network option before it is added.
	 *
	 * The dynamic portion of the hook name, `$option`, refers to the option name.
	 *
	 * @since 2.9.0 As 'pre_add_site_option_' . $key
	 * @since 3.0.0
	 * @since 4.4.0 The `$option` parameter was added.
	 * @since 4.7.0 The `$network_id` parameter was added.
	 *
	 * @param mixed  $value      Value of network option.
	 * @param string $option     Option name.
	 * @param int    $network_id ID of the network.
	 */
	$value = apply_filters("pre_add_site_option_{$option}", $value, $option, $network_id);

	$notoptions_key = "$network_id:notoptions";

	if (!is_multisite()) {
		$result = add_option($option, $value, '', 'no');
	} else {
		$cache_key = "$network_id:$option";

		// Make sure the option doesn't already exist.
		// We can check the 'notoptions' cache before we ask for a DB query.
		$notoptions = wp_cache_get($notoptions_key, 'site-options');

		if (!is_array($notoptions) || !isset($notoptions[$option])) {
			if (false !== get_network_option($network_id, $option, false)) {
				return false;
			}
		}

		$value = sanitize_option($option, $value);

		$serialized_value = maybe_serialize($value);
		$result           = $wpdb->insert(
			$wpdb->sitemeta,
			array(
				'site_id'    => $network_id,
				'meta_key'   => $option,
				'meta_value' => $serialized_value,
			)
		);

		if (!$result) {
			return false;
		}

		wp_cache_set($cache_key, $value, 'site-options');

		// This option exists now.
		$notoptions = wp_cache_get($notoptions_key, 'site-options'); // Yes, again... we need it to be fresh.

		if (is_array($notoptions) && isset($notoptions[$option])) {
			unset($notoptions[$option]);
			wp_cache_set($notoptions_key, $notoptions, 'site-options');
		}
	}

	if ($result) {

		/**
		 * Fires after a specific network option has been successfully added.
		 *
		 * The dynamic portion of the hook name, `$option`, refers to the option name.
		 *
		 * @since 2.9.0 As "add_site_option_{$key}"
		 * @since 3.0.0
		 * @since 4.7.0 The `$network_id` parameter was added.
		 *
		 * @param string $option     Name of the network option.
		 * @param mixed  $value      Value of the network option.
		 * @param int    $network_id ID of the network.
		 */
		do_action("add_site_option_{$option}", $option, $value, $network_id);

		/**
		 * Fires after a network option has been successfully added.
		 *
		 * @since 3.0.0
		 * @since 4.7.0 The `$network_id` parameter was added.
		 *
		 * @param string $option     Name of the network option.
		 * @param mixed  $value      Value of the network option.
		 * @param int    $network_id ID of the network.
		 */
		do_action('add_site_option', $option, $value, $network_id);

		return true;
	}

	return false;
}

/**
 * Removes a network option by name.
 *
 * @since 4.4.0
 *
 * @see delete_option()
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param int    $network_id ID of the network. Can be null to default to the current network ID.
 * @param string $option     Name of the option to delete. Expected to not be SQL-escaped.
 * @return bool True if the option was deleted, false otherwise.
 */
function delete_network_option($network_id, $option)
{
	global $wpdb;

	if ($network_id && !is_numeric($network_id)) {
		return false;
	}

	$network_id = (int) $network_id;

	// Fallback to the current network if a network ID is not specified.
	if (!$network_id) {
		$network_id = get_current_network_id();
	}

	/**
	 * Fires immediately before a specific network option is deleted.
	 *
	 * The dynamic portion of the hook name, `$option`, refers to the option name.
	 *
	 * @since 3.0.0
	 * @since 4.4.0 The `$option` parameter was added.
	 * @since 4.7.0 The `$network_id` parameter was added.
	 *
	 * @param string $option     Option name.
	 * @param int    $network_id ID of the network.
	 */
	do_action("pre_delete_site_option_{$option}", $option, $network_id);

	if (!is_multisite()) {
		$result = delete_option($option);
	} else {
		$row = $wpdb->get_row($wpdb->prepare("SELECT meta_id FROM {$wpdb->sitemeta} WHERE meta_key = %s AND site_id = %d", $option, $network_id));
		if (is_null($row) || !$row->meta_id) {
			return false;
		}
		$cache_key = "$network_id:$option";
		wp_cache_delete($cache_key, 'site-options');

		$result = $wpdb->delete(
			$wpdb->sitemeta,
			array(
				'meta_key' => $option,
				'site_id'  => $network_id,
			)
		);
	}

	if ($result) {

		/**
		 * Fires after a specific network option has been deleted.
		 *
		 * The dynamic portion of the hook name, `$option`, refers to the option name.
		 *
		 * @since 2.9.0 As "delete_site_option_{$key}"
		 * @since 3.0.0
		 * @since 4.7.0 The `$network_id` parameter was added.
		 *
		 * @param string $option     Name of the network option.
		 * @param int    $network_id ID of the network.
		 */
		do_action("delete_site_option_{$option}", $option, $network_id);

		/**
		 * Fires after a network option has been deleted.
		 *
		 * @since 3.0.0
		 * @since 4.7.0 The `$network_id` parameter was added.
		 *
		 * @param string $option     Name of the network option.
		 * @param int    $network_id ID of the network.
		 */
		do_action('delete_site_option', $option, $network_id);

		return true;
	}

	return false;
}

/**
 * Updates the value of a network option that was already added.
 *
 * @since 4.4.0
 *
 * @see update_option()
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param int    $network_id ID of the network. Can be null to default to the current network ID.
 * @param string $option     Name of the option. Expected to not be SQL-escaped.
 * @param mixed  $value      Option value. Expected to not be SQL-escaped.
 * @return bool True if the value was updated, false otherwise.
 */
function update_network_option($network_id, $option, $value)
{
	global $wpdb;

	if ($network_id && !is_numeric($network_id)) {
		return false;
	}

	$network_id = (int) $network_id;

	// Fallback to the current network if a network ID is not specified.
	if (!$network_id) {
		$network_id = get_current_network_id();
	}

	wp_protect_special_option($option);

	$old_value = get_network_option($network_id, $option, false);

	/**
	 * Filters a specific network option before its value is updated.
	 *
	 * The dynamic portion of the hook name, `$option`, refers to the option name.
	 *
	 * @since 2.9.0 As 'pre_update_site_option_' . $key
	 * @since 3.0.0
	 * @since 4.4.0 The `$option` parameter was added.
	 * @since 4.7.0 The `$network_id` parameter was added.
	 *
	 * @param mixed  $value      New value of the network option.
	 * @param mixed  $old_value  Old value of the network option.
	 * @param string $option     Option name.
	 * @param int    $network_id ID of the network.
	 */
	$value = apply_filters("pre_update_site_option_{$option}", $value, $old_value, $option, $network_id);

	/*
	 * If the new and old values are the same, no need to update.
	 *
	 * Unserialized values will be adequate in most cases. If the unserialized
	 * data differs, the (maybe) serialized data is checked to avoid
	 * unnecessary database calls for otherwise identical object instances.
	 *
	 * See https://core.trac.wordpress.org/ticket/44956
	 */
	if ($value === $old_value || maybe_serialize($value) === maybe_serialize($old_value)) {
		return false;
	}

	if (false === $old_value) {
		return add_network_option($network_id, $option, $value);
	}

	$notoptions_key = "$network_id:notoptions";
	$notoptions     = wp_cache_get($notoptions_key, 'site-options');

	if (is_array($notoptions) && isset($notoptions[$option])) {
		unset($notoptions[$option]);
		wp_cache_set($notoptions_key, $notoptions, 'site-options');
	}

	if (!is_multisite()) {
		$result = update_option($option, $value, 'no');
	} else {
		$value = sanitize_option($option, $value);

		$serialized_value = maybe_serialize($value);
		$result           = $wpdb->update(
			$wpdb->sitemeta,
			array('meta_value' => $serialized_value),
			array(
				'site_id'  => $network_id,
				'meta_key' => $option,
			)
		);

		if ($result) {
			$cache_key = "$network_id:$option";
			wp_cache_set($cache_key, $value, 'site-options');
		}
	}

	if ($result) {

		/**
		 * Fires after the value of a specific network option has been successfully updated.
		 *
		 * The dynamic portion of the hook name, `$option`, refers to the option name.
		 *
		 * @since 2.9.0 As "update_site_option_{$key}"
		 * @since 3.0.0
		 * @since 4.7.0 The `$network_id` parameter was added.
		 *
		 * @param string $option     Name of the network option.
		 * @param mixed  $value      Current value of the network option.
		 * @param mixed  $old_value  Old value of the network option.
		 * @param int    $network_id ID of the network.
		 */
		do_action("update_site_option_{$option}", $option, $value, $old_value, $network_id);

		/**
		 * Fires after the value of a network option has been successfully updated.
		 *
		 * @since 3.0.0
		 * @since 4.7.0 The `$network_id` parameter was added.
		 *
		 * @param string $option     Name of the network option.
		 * @param mixed  $value      Current value of the network option.
		 * @param mixed  $old_value  Old value of the network option.
		 * @param int    $network_id ID of the network.
		 */
		do_action('update_site_option', $option, $value, $old_value, $network_id);

		return true;
	}

	return false;
}

/**
 * Deletes a site transient.
 *
 * @since 2.9.0
 *
 * @param string $transient Transient name. Expected to not be SQL-escaped.
 * @return bool True if the transient was deleted, false otherwise.
 */
function delete_site_transient($transient)
{

	/**
	 * Fires immediately before a specific site transient is deleted.
	 *
	 * The dynamic portion of the hook name, `$transient`, refers to the transient name.
	 *
	 * @since 3.0.0
	 *
	 * @param string $transient Transient name.
	 */
	do_action("delete_site_transient_{$transient}", $transient);

	if (wp_using_ext_object_cache() || wp_installing()) {
		$result = wp_cache_delete($transient, 'site-transient');
	} else {
		$option_timeout = '_site_transient_timeout_' . $transient;
		$option         = '_site_transient_' . $transient;
		$result         = delete_site_option($option);

		if ($result) {
			delete_site_option($option_timeout);
		}
	}

	if ($result) {

		/**
		 * Fires after a transient is deleted.
		 *
		 * @since 3.0.0
		 *
		 * @param string $transient Deleted transient name.
		 */
		do_action('deleted_site_transient', $transient);
	}

	return $result;
}

/**
 * Retrieves the value of a site transient.
 *
 * If the transient does not exist, does not have a value, or has expired,
 * then the return value will be false.
 *
 * @since 2.9.0
 *
 * @see get_transient()
 *
 * @param string $transient Transient name. Expected to not be SQL-escaped.
 * @return mixed Value of transient.
 */
function get_site_transient($transient)
{

	/**
	 * Filters the value of an existing site transient before it is retrieved.
	 *
	 * The dynamic portion of the hook name, `$transient`, refers to the transient name.
	 *
	 * Returning a truthy value from the filter will effectively short-circuit retrieval
	 * and return the passed value instead.
	 *
	 * @since 2.9.0
	 * @since 4.4.0 The `$transient` parameter was added.
	 *
	 * @param mixed  $pre_site_transient The default value to return if the site transient does not exist.
	 *                                   Any value other than false will short-circuit the retrieval
	 *                                   of the transient, and return that value.
	 * @param string $transient          Transient name.
	 */
	$pre = apply_filters("pre_site_transient_{$transient}", false, $transient);

	if (false !== $pre) {
		return $pre;
	}

	if (wp_using_ext_object_cache() || wp_installing()) {
		$value = wp_cache_get($transient, 'site-transient');
	} else {
		// Core transients that do not have a timeout. Listed here so querying timeouts can be avoided.
		$no_timeout       = array('update_core', 'update_plugins', 'update_themes');
		$transient_option = '_site_transient_' . $transient;
		if (!in_array($transient, $no_timeout, true)) {
			$transient_timeout = '_site_transient_timeout_' . $transient;
			$timeout           = get_site_option($transient_timeout);
			if (false !== $timeout && $timeout < time()) {
				delete_site_option($transient_option);
				delete_site_option($transient_timeout);
				$value = false;
			}
		}

		if (!isset($value)) {
			$value = get_site_option($transient_option);
		}
	}

	/**
	 * Filters the value of an existing site transient.
	 *
	 * The dynamic portion of the hook name, `$transient`, refers to the transient name.
	 *
	 * @since 2.9.0
	 * @since 4.4.0 The `$transient` parameter was added.
	 *
	 * @param mixed  $value     Value of site transient.
	 * @param string $transient Transient name.
	 */
	return apply_filters("site_transient_{$transient}", $value, $transient);
}

/**
 * Sets/updates the value of a site transient.
 *
 * You do not need to serialize values. If the value needs to be serialized,
 * then it will be serialized before it is set.
 *
 * @since 2.9.0
 *
 * @see set_transient()
 *
 * @param string $transient  Transient name. Expected to not be SQL-escaped. Must be
 *                           167 characters or fewer in length.
 * @param mixed  $value      Transient value. Expected to not be SQL-escaped.
 * @param int    $expiration Optional. Time until expiration in seconds. Default 0 (no expiration).
 * @return bool True if the value was set, false otherwise.
 */
function set_site_transient($transient, $value, $expiration = 0)
{

	/**
	 * Filters the value of a specific site transient before it is set.
	 *
	 * The dynamic portion of the hook name, `$transient`, refers to the transient name.
	 *
	 * @since 3.0.0
	 * @since 4.4.0 The `$transient` parameter was added.
	 *
	 * @param mixed  $value     New value of site transient.
	 * @param string $transient Transient name.
	 */
	$value = apply_filters("pre_set_site_transient_{$transient}", $value, $transient);

	$expiration = (int) $expiration;

	/**
	 * Filters the expiration for a site transient before its value is set.
	 *
	 * The dynamic portion of the hook name, `$transient`, refers to the transient name.
	 *
	 * @since 4.4.0
	 *
	 * @param int    $expiration Time until expiration in seconds. Use 0 for no expiration.
	 * @param mixed  $value      New value of site transient.
	 * @param string $transient  Transient name.
	 */
	$expiration = apply_filters("expiration_of_site_transient_{$transient}", $expiration, $value, $transient);

	if (wp_using_ext_object_cache() || wp_installing()) {
		$result = wp_cache_set($transient, $value, 'site-transient', $expiration);
	} else {
		$transient_timeout = '_site_transient_timeout_' . $transient;
		$option            = '_site_transient_' . $transient;

		if (false === get_site_option($option)) {
			if ($expiration) {
				add_site_option($transient_timeout, time() + $expiration);
			}
			$result = add_site_option($option, $value);
		} else {
			if ($expiration) {
				update_site_option($transient_timeout, time() + $expiration);
			}
			$result = update_site_option($option, $value);
		}
	}

	if ($result) {

		/**
		 * Fires after the value for a specific site transient has been set.
		 *
		 * The dynamic portion of the hook name, `$transient`, refers to the transient name.
		 *
		 * @since 3.0.0
		 * @since 4.4.0 The `$transient` parameter was added
		 *
		 * @param mixed  $value      Site transient value.
		 * @param int    $expiration Time until expiration in seconds.
		 * @param string $transient  Transient name.
		 */
		do_action("set_site_transient_{$transient}", $value, $expiration, $transient);

		/**
		 * Fires after the value for a site transient has been set.
		 *
		 * @since 3.0.0
		 *
		 * @param string $transient  The name of the site transient.
		 * @param mixed  $value      Site transient value.
		 * @param int    $expiration Time until expiration in seconds.
		 */
		do_action('setted_site_transient', $transient, $value, $expiration);
	}

	return $result;
}

/**
 * Registers default settings available in WordPress.
 *
 * The settings registered here are primarily useful for the REST API, so this
 * does not encompass all settings available in WordPress.
 *
 * @since 4.7.0
 */
function register_initial_settings()
{
	register_setting(
		'general',
		'blogname',
		array(
			'show_in_rest' => array(
				'name' => 'title',
			),
			'type'         => 'string',
			'description'  => __('Site title.'),
		)
	);

	register_setting(
		'general',
		'blogdescription',
		array(
			'show_in_rest' => array(
				'name' => 'description',
			),
			'type'         => 'string',
			'description'  => __('Site tagline.'),
		)
	);

	if (!is_multisite()) {
		register_setting(
			'general',
			'siteurl',
			array(
				'show_in_rest' => array(
					'name'   => 'url',
					'schema' => array(
						'format' => 'uri',
					),
				),
				'type'         => 'string',
				'description'  => __('Site URL.'),
			)
		);
	}

	if (!is_multisite()) {
		register_setting(
			'general',
			'admin_email',
			array(
				'show_in_rest' => array(
					'name'   => 'email',
					'schema' => array(
						'format' => 'email',
					),
				),
				'type'         => 'string',
				'description'  => __('This address is used for admin purposes, like new user notification.'),
			)
		);
	}

	register_setting(
		'general',
		'timezone_string',
		array(
			'show_in_rest' => array(
				'name' => 'timezone',
			),
			'type'         => 'string',
			'description'  => __('A city in the same timezone as you.'),
		)
	);

	register_setting(
		'general',
		'date_format',
		array(
			'show_in_rest' => true,
			'type'         => 'string',
			'description'  => __('A date format for all date strings.'),
		)
	);

	register_setting(
		'general',
		'time_format',
		array(
			'show_in_rest' => true,
			'type'         => 'string',
			'description'  => __('A time format for all time strings.'),
		)
	);

	register_setting(
		'general',
		'start_of_week',
		array(
			'show_in_rest' => true,
			'type'         => 'integer',
			'description'  => __('A day number of the week that the week should start on.'),
		)
	);

	register_setting(
		'general',
		'WPLANG',
		array(
			'show_in_rest' => array(
				'name' => 'language',
			),
			'type'         => 'string',
			'description'  => __('WordPress locale code.'),
			'default'      => 'en_US',
		)
	);

	register_setting(
		'writing',
		'use_smilies',
		array(
			'show_in_rest' => true,
			'type'         => 'boolean',
			'description'  => __('Convert emoticons like :-) and :-P to graphics on display.'),
			'default'      => true,
		)
	);

	register_setting(
		'writing',
		'default_category',
		array(
			'show_in_rest' => true,
			'type'         => 'integer',
			'description'  => __('Default post category.'),
		)
	);

	register_setting(
		'writing',
		'default_post_format',
		array(
			'show_in_rest' => true,
			'type'         => 'string',
			'description'  => __('Default post format.'),
		)
	);

	register_setting(
		'reading',
		'posts_per_page',
		array(
			'show_in_rest' => true,
			'type'         => 'integer',
			'description'  => __('Blog pages show at most.'),
			'default'      => 10,
		)
	);

	register_setting(
		'discussion',
		'default_ping_status',
		array(
			'show_in_rest' => array(
				'schema' => array(
					'enum' => array('open', 'closed'),
				),
			),
			'type'         => 'string',
			'description'  => __('Allow link notifications from other blogs (pingbacks and trackbacks) on new articles.'),
		)
	);

	register_setting(
		'discussion',
		'default_comment_status',
		array(
			'show_in_rest' => array(
				'schema' => array(
					'enum' => array('open', 'closed'),
				),
			),
			'type'         => 'string',
			'description'  => __('Allow people to submit comments on new posts.'),
		)
	);
}

/**
 * Registers a setting and its data.
 *
 * @since 2.7.0
 * @since 3.0.0 The `misc` option group was deprecated.
 * @since 3.5.0 The `privacy` option group was deprecated.
 * @since 4.7.0 `$args` can be passed to set flags on the setting, similar to `register_meta()`.
 * @since 5.5.0 `$new_whitelist_options` was renamed to `$new_allowed_options`.
 *              Please consider writing more inclusive code.
 *
 * @global array $new_allowed_options
 * @global array $wp_registered_settings
 *
 * @param string $option_group A settings group name. Should correspond to an allowed option key name.
 *                             Default allowed option key names include 'general', 'discussion', 'media',
 *                             'reading', 'writing', and 'options'.
 * @param string $option_name The name of an option to sanitize and save.
 * @param array  $args {
 *     Data used to describe the setting when registered.
 *
 *     @type string     $type              The type of data associated with this setting.
 *                                         Valid values are 'string', 'boolean', 'integer', 'number', 'array', and 'object'.
 *     @type string     $description       A description of the data attached to this setting.
 *     @type callable   $sanitize_callback A callback function that sanitizes the option's value.
 *     @type bool|array $show_in_rest      Whether data associated with this setting should be included in the REST API.
 *                                         When registering complex settings, this argument may optionally be an
 *                                         array with a 'schema' key.
 *     @type mixed      $default           Default value when calling `get_option()`.
 * }
 */
function register_setting($option_group, $option_name, $args = array())
{
	global $new_allowed_options, $wp_registered_settings;

	/*
	 * In 5.5.0, the `$new_whitelist_options` global variable was renamed to `$new_allowed_options`.
	 * Please consider writing more inclusive code.
	 */
	$GLOBALS['new_whitelist_options'] = &$new_allowed_options;

	$defaults = array(
		'type'              => 'string',
		'group'             => $option_group,
		'description'       => '',
		'sanitize_callback' => null,
		'show_in_rest'      => false,
	);

	// Back-compat: old sanitize callback is added.
	if (is_callable($args)) {
		$args = array(
			'sanitize_callback' => $args,
		);
	}

	/**
	 * Filters the registration arguments when registering a setting.
	 *
	 * @since 4.7.0
	 *
	 * @param array  $args         Array of setting registration arguments.
	 * @param array  $defaults     Array of default arguments.
	 * @param string $option_group Setting group.
	 * @param string $option_name  Setting name.
	 */
	$args = apply_filters('register_setting_args', $args, $defaults, $option_group, $option_name);

	$args = wp_parse_args($args, $defaults);

	// Require an item schema when registering settings with an array type.
	if (false !== $args['show_in_rest'] && 'array' === $args['type'] && (!is_array($args['show_in_rest']) || !isset($args['show_in_rest']['schema']['items']))) {
		_doing_it_wrong(__FUNCTION__, __('When registering an "array" setting to show in the REST API, you must specify the schema for each array item in "show_in_rest.schema.items".'), '5.4.0');
	}

	if (!is_array($wp_registered_settings)) {
		$wp_registered_settings = array();
	}

	if ('misc' === $option_group) {
		_deprecated_argument(
			__FUNCTION__,
			'3.0.0',
			sprintf(
				/* translators: %s: misc */
				__('The "%s" options group has been removed. Use another settings group.'),
				'misc'
			)
		);
		$option_group = 'general';
	}

	if ('privacy' === $option_group) {
		_deprecated_argument(
			__FUNCTION__,
			'3.5.0',
			sprintf(
				/* translators: %s: privacy */
				__('The "%s" options group has been removed. Use another settings group.'),
				'privacy'
			)
		);
		$option_group = 'reading';
	}

	$new_allowed_options[$option_group][] = $option_name;

	if (!empty($args['sanitize_callback'])) {
		add_filter("sanitize_option_{$option_name}", $args['sanitize_callback']);
	}
	if (array_key_exists('default', $args)) {
		add_filter("default_option_{$option_name}", 'filter_default_option', 10, 3);
	}

	/**
	 * Fires immediately before the setting is registered but after its filters are in place.
	 *
	 * @since 5.5.0
	 *
	 * @param string $option_group Setting group.
	 * @param string $option_name  Setting name.
	 * @param array  $args         Array of setting registration arguments.
	 */
	do_action('register_setting', $option_group, $option_name, $args);

	$wp_registered_settings[$option_name] = $args;
}

/**
 * Unregisters a setting.
 *
 * @since 2.7.0
 * @since 4.7.0 `$sanitize_callback` was deprecated. The callback from `register_setting()` is now used instead.
 * @since 5.5.0 `$new_whitelist_options` was renamed to `$new_allowed_options`.
 *              Please consider writing more inclusive code.
 *
 * @global array $new_allowed_options
 * @global array $wp_registered_settings
 *
 * @param string   $option_group The settings group name used during registration.
 * @param string   $option_name  The name of the option to unregister.
 * @param callable $deprecated   Optional. Deprecated.
 */
function unregister_setting($option_group, $option_name, $deprecated = '')
{
	global $new_allowed_options, $wp_registered_settings;

	/*
	 * In 5.5.0, the `$new_whitelist_options` global variable was renamed to `$new_allowed_options`.
	 * Please consider writing more inclusive code.
	 */
	$GLOBALS['new_whitelist_options'] = &$new_allowed_options;

	if ('misc' === $option_group) {
		_deprecated_argument(
			__FUNCTION__,
			'3.0.0',
			sprintf(
				/* translators: %s: misc */
				__('The "%s" options group has been removed. Use another settings group.'),
				'misc'
			)
		);
		$option_group = 'general';
	}

	if ('privacy' === $option_group) {
		_deprecated_argument(
			__FUNCTION__,
			'3.5.0',
			sprintf(
				/* translators: %s: privacy */
				__('The "%s" options group has been removed. Use another settings group.'),
				'privacy'
			)
		);
		$option_group = 'reading';
	}

	$pos = array_search($option_name, (array) $new_allowed_options[$option_group], true);

	if (false !== $pos) {
		unset($new_allowed_options[$option_group][$pos]);
	}

	if ('' !== $deprecated) {
		_deprecated_argument(
			__FUNCTION__,
			'4.7.0',
			sprintf(
				/* translators: 1: $sanitize_callback, 2: register_setting() */
				__('%1$s is deprecated. The callback from %2$s is used instead.'),
				'<code>$sanitize_callback</code>',
				'<code>register_setting()</code>'
			)
		);
		remove_filter("sanitize_option_{$option_name}", $deprecated);
	}

	if (isset($wp_registered_settings[$option_name])) {
		// Remove the sanitize callback if one was set during registration.
		if (!empty($wp_registered_settings[$option_name]['sanitize_callback'])) {
			remove_filter("sanitize_option_{$option_name}", $wp_registered_settings[$option_name]['sanitize_callback']);
		}

		// Remove the default filter if a default was provided during registration.
		if (array_key_exists('default', $wp_registered_settings[$option_name])) {
			remove_filter("default_option_{$option_name}", 'filter_default_option', 10);
		}

		/**
		 * Fires immediately before the setting is unregistered and after its filters have been removed.
		 *
		 * @since 5.5.0
		 *
		 * @param string $option_group Setting group.
		 * @param string $option_name  Setting name.
		 */
		do_action('unregister_setting', $option_group, $option_name);

		unset($wp_registered_settings[$option_name]);
	}
}

/**
 * Retrieves an array of registered settings.
 *
 * @since 4.7.0
 *
 * @global array $wp_registered_settings
 *
 * @return array List of registered settings, keyed by option name.
 */
function get_registered_settings()
{
	global $wp_registered_settings;

	if (!is_array($wp_registered_settings)) {
		return array();
	}

	return $wp_registered_settings;
}

/**
 * Filters the default value for the option.
 *
 * For settings which register a default setting in `register_setting()`, this
 * function is added as a filter to `default_option_{$option}`.
 *
 * @since 4.7.0
 *
 * @param mixed  $default        Existing default value to return.
 * @param string $option         Option name.
 * @param bool   $passed_default Was `get_option()` passed a default value?
 * @return mixed Filtered default value.
 */
function filter_default_option($default, $option, $passed_default)
{
	if ($passed_default) {
		return $default;
	}

	$registered = get_registered_settings();
	if (empty($registered[$option])) {
		return $default;
	}

	return $registered[$option]['default'];
}
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