code: func (s *Serializer) RecognizesData(peek io.Reader) (bool, bool, error) {
  	prefix := make([]byte, 4)
  	n, err := peek.Read(prefix)
  	if err != nil {
  		if err == io.EOF {
  			return false, false, nil
  		}
  		return false, false, err
  	}
  	if n != 4 {
  		return false, false, nil
  	}
  	return bytes.Equal(s.prefix, prefix), false, nil
  }
docs: // RecognizesData implements the RecognizingDecoder interface.