code: func SignatureString(alg x509.SignatureAlgorithm) string {
  	switch alg {
  	case x509.MD2WithRSA:
  		return "MD2WithRSA"
  	case x509.MD5WithRSA:
  		return "MD5WithRSA"
  	case x509.SHA1WithRSA:
  		return "SHA1WithRSA"
  	case x509.SHA256WithRSA:
  		return "SHA256WithRSA"
  	case x509.SHA384WithRSA:
  		return "SHA384WithRSA"
  	case x509.SHA512WithRSA:
  		return "SHA512WithRSA"
  	case x509.DSAWithSHA1:
  		return "DSAWithSHA1"
  	case x509.DSAWithSHA256:
  		return "DSAWithSHA256"
  	case x509.ECDSAWithSHA1:
  		return "ECDSAWithSHA1"
  	case x509.ECDSAWithSHA256:
  		return "ECDSAWithSHA256"
  	case x509.ECDSAWithSHA384:
  		return "ECDSAWithSHA384"
  	case x509.ECDSAWithSHA512:
  		return "ECDSAWithSHA512"
  	default:
  		return "Unknown Signature"
  	}
  }
docs: // SignatureString returns the TLS signature string corresponding to
  // an X509 signature algorithm.