code: func ParsePublicKeyPEM(bytes []byte) (interface{}, error) {
  	block, _ := pem.Decode(bytes)
  	if block == nil {
  		return nil, trace.BadParameter("expected PEM-encoded block")
  	}
  	return ParsePublicKeyDER(block.Bytes)
  }
docs: // ParsePublicKeyPEM parses public key PEM