code: func newHashFromStr(hexStr string) *chainhash.Hash {
  	hash, err := chainhash.NewHashFromStr(hexStr)
  	if err != nil {
  		// Ordinarily I don't like panics in library code since it
  		// can take applications down without them having a chance to
  		// recover which is extremely annoying, however an exception is
  		// being made in this case because the only way this can panic
  		// is if there is an error in the hard-coded hashes.  Thus it
  		// will only ever potentially panic on init and therefore is
  		// 100% predictable.
  		panic(err)
  	}
  	return hash
  }
docs: // newHashFromStr converts the passed big-endian hex string into a
  // chainhash.Hash.  It only differs from the one available in chainhash in that
  // it panics on an error since it will only (and must only) be called with
  // hard-coded, and therefore known good, hashes.