boolean. Should return True if the value provided is considered valid. May
      contain a complex error message if error_msg does not provide enough
      information. In that case, set suppress_default_error to True.
    error_msg: (String) String with one and only one '%s'. Formatted with each
      invalid response upon check_success(input) failure.

            if response.status != 200:
                message = "Credential refresh failed, response: %s"
                raise CredentialRetrievalError(
                    provider=method,
                    error_msg=message % response.status,
                )

            creds = json.loads(response.data)

            query = {}
            query['Action'] = 'AssumeRoleWithClientGrants'