Checks if an API Gateway integration is already present at the given path/method

        :param string path: Path name
        :param string method: HTTP method
        :return: True, if an API Gateway integration is already present

def has_integration(self, path, method):
        """
        Checks if an API Gateway integration is already present at the given path/method

        :param string path: Path name
        :param string method: HTTP method
        :return: True, if an API Gateway integration is already present
        """
        method = self._normalize_method_name(method)

        path_dict = self.get_path(path)
        return self.has_path(path, method) and \
            isinstance(path_dict[method], dict) and \
            self.method_has_integration(path_dict[method])