def delete(self, doc):
        if doc.id is None:
            raise DatabaseException('Document does not have id')
        if doc.sid is None:
            try:
                rs = self.db.docs.remove({'id': doc.id}, safe=True)
                assert rs['n'] == 1
            except Exception as e:
                raise DatabaseException(e)
            return None
        doc.data = None
        return self.update(doc)
def draw(self, context):
        props = self.layout.operator("wm.context_set_value", text="Blender (default)")
        props.data_path = "window_manager.keyconfigs.active"
        props.value = "context.window_manager.keyconfigs.default"

        # now draw the presets
        Menu.draw_preset(self, context)