code: func (s *UIServerAPI) OpenWallet(url string, passphrase *string) error {
  	wallet, err := s.am.Wallet(url)
  	if err != nil {
  		return err
  	}
  	pass := ""
  	if passphrase != nil {
  		pass = *passphrase
  	}
  	return wallet.Open(pass)
  }
docs: // OpenWallet initiates a hardware wallet opening procedure, establishing a USB
  // connection and attempting to authenticate via the provided passphrase. Note,
  // the method may return an extra challenge requiring a second open (e.g. the
  // Trezor PIN matrix challenge).
  // Example
  // {"jsonrpc":"2.0","method":"clef_openWallet","params":["ledger://",""], "id":6}