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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 to_xml(self):
 """Convert this ResourceRecordSet into XML to be saved via the ChangeResourceRecordSetsRequest"""

        changesXML = ""
        for change in self.changes:
            changeParams = {"action": change[0], "record": change[1].to_xml()}
            changesXML += self.ChangeXML % changeParams
        params = {"comment": self.comment, "changes": changesXML}
        return self.ChangeResourceRecordSetsBody % params