def add_choice(self, name, func, label):
        assert not name in self.choices_dict
        allowed_names = ("yes", "no", "ok", "cancel")
        if not name in allowed_names:
            raise Exception("Sorry, name must be one of %s" % allowed_names)
        cbc = CallbackChoice(name, func, label)
        self.choices.append(cbc)
        self.choices_dict[name] = cbc
        return cbc
Add a possible answer to this callback.
dataset/ETHPy150Open lsaffre/lino/lino/core/kernel.py/Callback.add_choice