def __getattr__(self, attr):
        if self.__defaults.keys() not in attr:
            raise AttributeError("Invalid API setting: '%s'" % attr)

        try:
            # Check if user have set that key.
            val = self.__user_settings[attr]
        except KeyError:
            # Use defaults otherwise.
            val = self.__defaults[attr]

        return val
dataset/ETHPy150Open facebook/augmented-traffic-control/atc/django-atc-demo-ui/atc_demo_ui/settings.py/APISettings.__getattr__/swapped operands of `not in`