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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_ip_unnumbered(self, unnumbered_type, unnumbered_name):
 """Get and merge the `ip unnumbered` config from an interface. You should not use this method. You probably want `Interface.ip_unnumbered`. Args: unnumbered_type: XML document with the XML to get the donor type. unnumbered_name: XML document with the XML to get the donor name. Returns: Merged XML document. Raises: None """

        unnumbered_type = self._callback(unnumbered_type, handler='get_config')
        unnumbered_name = self._callback(unnumbered_name, handler='get_config')
        unnumbered_type = pynos.utilities.return_xml(str(unnumbered_type))
        unnumbered_name = pynos.utilities.return_xml(str(unnumbered_name))
        return pynos.utilities.merge_xml(unnumbered_type, unnumbered_name)