code: func (z *Writer) Reset(w io.Writer) {
  	z.Header = Header{}
  	z.dst = w
  	z.checksum.Reset()
  	z.zdata = z.zdata[:0]
  	z.data = z.data[:0]
  	z.idx = 0
  }
docs: // Reset clears the state of the Writer z such that it is equivalent to its
  // initial state from NewWriter, but instead writing to w.
  // No access to the underlying io.Writer is performed.