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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 get_xml_str(self, data):
 """ Creates a string in XML Format using the provided data structure. @param: Dictionary of xml tags and their elements. @return: String of data in xml format. """


        responses = []
        for tag, value in data.items():
            elem = Element(tag)
            if isinstance(value, dict):
                for value in self.get_xml_str(value):
                    elem.append(value)
            elif isinstance(value, list):
                value = ', '.join([m for m in value])
                elem.text = value
            else:
                elem.text = value
            responses.append(elem)
        return responses