code: def parse_error(self, response):
          " Parse authentication errors."
  
          # Check invalid credentials.
          if self.check_error(response, 'failure', 'INVALID_DATA'):
              raise self.CredentialsError(
                  self.response_message(response, 'ERROR')f parse_error(self, response):
          " Parse authentication errors."
  
          # Check invalid credentials.
          if self.check_error(response, 'failure', 'INVALID_DATA'):
              raise self.CredentialsError(
                  self.response_message(response, 'ERROR'))
docs: Parse authentication errors.