code: def _execute(self, command, data=None, unpack=True):
          
          if not data:
              data = {}
          if self.session_id is not None:
              data.setdefault('session_id', self.session_id)
          data = self._wrap_el(data)
          res = self.remote_invoker.execute(command, data)
          ret = WebDriverResult.from_object(res)
          ret.raise_for_status()
          ret.value = self._unwrap_el(ret.value)
          if not unpack:
              return ret
          return ret.value
docs: Private method to execute command.
  
          Args:
              command(Command): The defined command.
              data(dict): The uri variable and body.
              uppack(bool): If unpack value from result.
  
          Returns:
              The unwrapped value field in the json response.