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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def assert_event(self, txn_hash, event_name, args, timeout=5):
 """ Assert that `event_name` is emitted with the `args` For use in tests only. """

        def assert_args(event):
            assert event['args'] == args, f'{event["args"]} == {args}'
        self.add(txn_hash=txn_hash, event_name=event_name, callback=assert_args)
        self.check(timeout=timeout)