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

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