code: func (uc *UpstreamConfig) ConnectTimeout() time.Duration {
  	if ms, ok := uc.Config["connect_timeout_ms"].(int); ok {
  		return time.Duration(ms) * time.Millisecond
  	}
  	return 10000 * time.Millisecond
  }
docs: // ConnectTimeout returns the connect timeout field of the nested config struct
  // or the default value.