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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 put_request_payment(self, bucket, payer):
 """ Set request payment configuration on bucket to payer. @param bucket: The name of the bucket. @param payer: The name of the payer. @return: A C{Deferred} that will fire with the result of the request. """

        data = RequestPayment(payer).to_xml()
        details = self._details(
            method=b"PUT",
            url_context=self._url_context(bucket=bucket, object_name="?requestPayment"),
            body=data,
        )
        d = self._submit(self._query_factory(details))
        return d