exists(). * * @param string $username * @return UserInterface */ public function load($username): UserInterface; /** * Find a user by username, email, etc * * @param string $query the query to search for * @param array $fields the fields to search * @return UserInterface */ public function find($query, $fields = ['username', 'email']): UserInterface; /** * Delete user account. * * @param string $username * @return bool True if user account was found and was deleted. */ public function delete($username): bool; }