code: def call(self, method, *args):
          
  
          payload = self.build_payload(method, args)
          logging.debug('* Client will send payload: {}'.format(payload))
          self.send(payload)
  
          res = self.receive()
          assert payload[2] == res['ref']
          return res['result'], res['error']
docs: Make a call to a `Responder` and return the result