code: func (resp *CopStreamResponse) Recv() (*coprocessor.Response, error) {
  	deadline := time.Now().Add(resp.Timeout).UnixNano()
  	atomic.StoreInt64(&resp.Lease.deadline, deadline)
  
  	ret, err := resp.Tikv_CoprocessorStreamClient.Recv()
  
  	atomic.StoreInt64(&resp.Lease.deadline, 0) // Stop the lease check.
  	return ret, errors.Trace(err)
  }
docs: // Recv overrides the stream client Recv() function.