code: def auth_token(self, apikey=None, secret=None, email=None, password=None):
          
          if (apikey and secret) or (self._apikey and self._secret):
              body = {
                  "key_id": apikey or self._apikey,
                  "secret": secret or self._secret
              }
          elif (email and password) or (self._email and self._password):
              body = {
                  "user" : email or self._email,
                  "password" : password or self._password
              }
          else:
              raise Value("No authentication provided.")
          response = self._post(url.auth, body=body)
  
          self._check_response(response, 200)
          return self._create_response(response).get("jwt")
docs: Get authentication token.  Uses POST to /auth interface.
  
          :Returns: (str) Authentication JWT