code: func (c *Client) LogIn(user string, pass string, lang string) (err error) {
  	c.Login = user
  	c.Password = pass
  	c.Language = lang
  	args := []interface{}{user, pass, lang, c.UserAgent}
  	res := struct {
  		Status string `xmlrpc:"status"`
  		Token  string `xmlrpc:"token"`
  	}{}
  	if err = c.Call("LogIn", args, &res); err != nil {
  		return
  	}
  
  	if res.Status != StatusSuccess {
  		return fmt.Errorf("Login: %s", res.Status)
  	}
  	c.Token = res.Token
  	return
  }
docs: // LogIn to the API, and return a session token.