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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 run_fn_atomically(self, request):
 """Execute a function, atomically and reply with the result."""

        fn = serializer.loads_fn(request[Msgs.info])
        args, kwargs = request[Msgs.args], request[Msgs.kwargs]
        with self.mutate_safely():
            self.reply(fn(self.state, *args, **kwargs))