code: def _post(self, url, data=None):
          
          url = urljoin(self.base_url, url)
          try:
              r = self._make_request(**dict(
                  method='POST',
                  url=url,
                  json=data,
                  auth=self.auth,
                  timeout=self.timeout,
                  hooks=self.request_hooks,
                  headers=self.request_headers
              ))
          except requests.exceptions.RequestException as e:
              raise e
          else:
              if r.status_code >= 400:
                  # in case of a 500 error, the response might not be a JSON
                  try:
                      error_data = r.json()
                  except ValueError:
                      error_data = { "response": r }
                  raise MailChimpError(error_data)
              if r.status_code == 204:
                  return None
              return r.json()
docs: Handle authenticated POST requests
  
          :param url: The url for the endpoint including path parameters
          :type url: :py:class:`str`
          :param data: The request body parameters
          :type data: :py:data:`none` or :py:class:`dict`
          :returns: The JSON output from the API or an error message