def get_unit_conversion_session(self):
raise Unimplemented()<EOL>
Gets a unit conversion session.

        return: (osid.locale.UnitConversionSession) - a
                ``UnitConversionSession``
        raise:  OperationFailed - unable to complete request
        raise:  Unimplemented - ``supports_unit_conversion()`` is
                ``false``
        *compliance: optional -- This method must be implemented if
        ``supports_unit_conversion()`` is ``true``.*