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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 xrp_withdrawal(self, amount, address, destination_tag=None):
 """ Sends xrps to another xrp wallet specified by address. Returns withdrawal id. """

        data = {'amount': amount, 'address': address}
        if destination_tag:
            data['destination_tag'] = destination_tag

        return self._post("xrp_withdrawal/", data=data, return_json=True,
                          version=2)["id"]