code: func Keccak256Hash(data ...[]byte) (h common.Hash) {
  	d := sha3.NewLegacyKeccak256()
  	for _, b := range data {
  		d.Write(b)
  	}
  	d.Sum(h[:0])
  	return h
  }
docs: // Keccak256Hash calculates and returns the Keccak256 hash of the input data,
  // converting it to an internal Hash data structure.