code: func MakeChannelHeader(headerType cb.HeaderType, version int32, chainID string, epoch uint64) *cb.ChannelHeader {
  	return &cb.ChannelHeader{
  		Type:    int32(headerType),
  		Version: version,
  		Timestamp: &timestamp.Timestamp{
  			Seconds: time.Now().Unix(),
  			Nanos:   0,
  		},
  		ChannelId: chainID,
  		Epoch:     epoch,
  	}
  }
docs: // MakeChannelHeader creates a ChannelHeader.