def allow_relation(self, obj1, obj2, **hints):
    '\n        Allow relations if a model in the app is involved.\n        '
    if ((obj1._meta.app_label in self.apps) or (obj2._meta.app_label in self.apps)):
        return True
    return None
Allow relations if a model in the app is involved.
def allow_relation(self, obj1, obj2, **hints):
    '\n        \n        '
    if ((obj1._meta.app_label in self.apps) or (obj2._meta.app_label in self.apps)):
        return True
    return None