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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:
 async def get_object_proxy_location(self, client, pid):
 """If object is proxied, return the proxy location URL. If object is local, return None. """

        try:
            return (await client.describe(pid)).get("DataONE-Proxy")
        except d1_common.types.exceptions.DataONEException:
            # Workaround for older GMNs that return 500 instead of 404 for describe()
            pass