code: func UnmarshalChannelHeader(bytes []byte) (*cb.ChannelHeader, error) {
  	chdr := &cb.ChannelHeader{}
  	err := proto.Unmarshal(bytes, chdr)
  	return chdr, errors.Wrap(err, "error unmarshaling ChannelHeader")
  }
docs: // UnmarshalChannelHeader returns a ChannelHeader from bytes