code: func NewHash(newHash []byte) (*Hash, error) {
  	var sh Hash
  	err := sh.SetBytes(newHash)
  	if err != nil {
  		return nil, err
  	}
  	return &sh, err
  }
docs: // NewHash returns a new Hash from a byte slice.  An error is returned if
  // the number of bytes passed in is not HashSize.