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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 _should_proxy(self, attr):
 """ Determines whether `attr` should be looked up on the proxied object, or the proxy itself. """

        if attr in type(self).__notproxied__:
            return False
        if _oga(self, "__notproxied__") is True:
            return False
        return True