public static function verify_scope($received_scope, $requested_scope='user:email') {
	if (strpos($received_scope, $requested_scope) !== false) {
		return true;
	}
	
	if (strpos($requested_scope, ':')) {
		$parent_requested_scope = substr($requested_scope, 0, strpos($requested_scope, ':'));
		if (strpos($received_scope, $parent_requested_scope) !== false) {
			return true;
		}
	}
	
	return false;
}