ensure_subscription.py

def ensure_subscription(fn):
    @wraps(fn)
    def _ensure_subscription(user, other, trade):
        unsubscribe_code = user.profile.get_unsubscribe_code('trade-notifications')
        if unsubscribe_code is None:
            return
        fn_globals = {}
        fn_globals.update(globals())
        fn_globals['unsubscribe_code'] = unsubscribe_code
        call_fn = FunctionType(fn.func_code, fn_globals)
        return call_fn(user, other, trade)
    return _ensure_subscription