* @param string $tag Used in counting how many hooks were applied
* @param callback $function Used for creating unique id
* @param int|bool $priority Used in counting how many hooks were applied. If === false and $function is an object reference, we return the unique id only if it already has one, false otherwise.
* @param string $tag Used in counting how many hooks were applied
* @param callback $function Used for creating unique id
* @param int|bool $priority Used in counting how many hooks were applied. If === false and $function is an object reference, we return the unique id only if it already has one, false otherwise.