code: func Ecrecover(hash, sig []byte) ([]byte, error) {
  	pub, err := SigToPub(hash, sig)
  	if err != nil {
  		return nil, err
  	}
  	bytes := (*btcec.PublicKey)(pub).SerializeUncompressed()
  	return bytes, err
  }
docs: // Ecrecover returns the uncompressed public key that created the given signature.