@classmethod
def after_create_instance(cls, obj, ar):
    """

        A hook for code to be executed when a new instance has been created in
        this table.

        This is for actor-specific behaviour.  You can do the equivalent for
        every table on a model by defining an :meth:`after_ui_create
        <lino.core.model.Model.after_ui_create>` method on the model.

        Usage example: :class:`lino_xl.lib.cal.GuestsByPartner`.

        """
    pass
