code: func parseECPrivateKey(data []byte) (*ecdsa.PrivateKey, error) {
  	var err error
  
  	// Parse the key
  	var parsedKey interface{}
  	if parsedKey, err = x509.ParseECPrivateKey(data); err != nil {
  		return nil, err
  	}
  
  	// Test if parsed key is an ECDSA Private Key
  	var privKey *ecdsa.PrivateKey
  	var ok bool
  	if privKey, ok = parsedKey.(*ecdsa.PrivateKey); !ok {
  		return nil, fmt.Errorf("data doesn't contain valid ECDSA Private Key")
  	}
  
  	return privKey, nil
  }
docs: // parseECPrivateKey parses a single ECDSA private key from the provided data