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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 refund(self, **kwargs):
 """Refund this transaction. Calling this method returns the refunded transaction (that is, ``self``) if the refund was successful, or raises a `ResponseError` if an error occurred requesting the refund. After a successful call to `refund()`, to retrieve the new transaction representing the refund, use the `get_refund_transaction()` method. """

        # Find the URL and method to refund the transaction.
        try:
            selfnode = self._elem
        except AttributeError:
            raise AttributeError('refund')
        url, method = None, None
        for anchor_elem in selfnode.findall('a'):
            if anchor_elem.attrib.get('name') == 'refund':
                url = anchor_elem.attrib['href']
                method = anchor_elem.attrib['method'].upper()
        if url is None or method is None:
            raise AttributeError("refund")  # should do something more specific probably

        actionator = self._make_actionator(url, method, extra_handler=self._handle_refund_accepted)
        return actionator(**kwargs)