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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 _create_xml_node(cls):
 """Create XML node from "_xml_map". """

        try:
            xml_map = cls._xml_map
        except AttributeError:
            raise ValueError("This model has no XML definition")

        return _create_xml_node(
            xml_map.get('name', cls.__name__),
            xml_map.get("prefix", None),
            xml_map.get("ns", None)
        )