code: def _send_request(self, operation, url, payload, desc):
          
  
          res = None
          try:
              payload_json = None
              if payload and payload != '':
                  payload_json = jsonutils.dumps(payload)
              self._login()
              desc_lookup = {'POST': ' creation', 'PUT': ' update',
                             'DELETE': ' deletion', 'GET': ' get'}
  
              res = requests.request(operation, url, data=payload_json,
                                     headers=self._req_headers,
                                     timeout=self.timeout_resp, verify=False)
              desc += desc_lookup.get(operation, operation.lower())
              LOG.info("DCNM-send_request: %(desc)s %(url)s %(pld)s",
                       {'desc': desc, 'url': url, 'pld': payload})
  
              self._logout()
          except (requests.HTTPError, requests.Timeout,
                  requests.ConnectionError) as exc:
              LOG.exception('Error during request: %s', exc)
              raise dexc.DfaClientRequestFailed(reason=exc)
  
          return res
docs: Send request to DCNM.