code: func (f *Function) BuildBytes() ([]byte, error) {
  	r, err := f.Build()
  	if err != nil {
  		return nil, err
  	}
  
  	b, err := ioutil.ReadAll(r)
  	if err != nil {
  		return nil, err
  	}
  
  	f.Log.Debugf("created build (%s)", humanize.Bytes(uint64(len(b))))
  	return b, nil
  }
docs: // BuildBytes returns the generated zip as bytes.