code: func New(ctx context.Context) (*GPG, error) {
  	pubfn := filepath.Join(gpgHome(ctx), "pubring.gpg")
  	pubring, err := readKeyring(pubfn)
  	if err != nil {
  		return nil, err
  	}
  	secfn := filepath.Join(gpgHome(ctx), "secring.gpg")
  	secring, err := readKeyring(secfn)
  	if err != nil {
  		return nil, err
  	}
  	g := &GPG{
  		pubring: pubring,
  		secring: secring,
  		pubfn:   pubfn,
  		secfn:   secfn,
  	}
  	return g, nil
  }
docs: // New creates a new pure-Go GPG backend