code: func (i *TeleInstance) NewClientWithCreds(cfg ClientConfig, creds UserCreds) (tc *client.TeleportClient, err error) {
  	clt, err := i.NewUnauthenticatedClient(cfg)
  	if err != nil {
  		return nil, trace.Wrap(err)
  	}
  	err = SetupUserCreds(clt, i.Config.Proxy.SSHAddr.Addr, creds)
  	if err != nil {
  		return nil, trace.Wrap(err)
  	}
  	return clt, nil
  }
docs: // NewClientWithCreds creates client with credentials