code: func (ch *Channel) Flow(active bool) error {
  	return ch.call(
  		&channelFlow{Active: active},
  		&channelFlowOk{},
  	)
  }
docs: /*
  Flow pauses the delivery of messages to consumers on this channel.  Channels
  are opened with flow control active, to open a channel with paused
  deliveries immediately call this method with `false` after calling
  Connection.Channel.
  
  When active is `false`, this method asks the server to temporarily pause deliveries
  until called again with active as `true`.
  
  Channel.Get methods will not be affected by flow control.
  
  This method is not intended to act as window control.  Use Channel.Qos to limit
  the number of unacknowledged messages or bytes in flight instead.
  
  The server may also send us flow methods to throttle our publishings.  A well
  behaving publishing client should add a listener with Channel.NotifyFlow and
  pause its publishings when `false` is sent on that channel.
  
  Note: RabbitMQ prefers to use TCP push back to control flow for all channels on
  a connection, so under high volume scenarios, it's wise to open separate
  Connections for publishings and deliveries.
  
  */