def unpack_polygons(polygons: Sequence[Polygon],
context: Context) -> Union[Empty, Multipolygon, Polygon]:
return ((context.multipolygon_cls(polygons)
if len(polygons) > 1
else polygons[0])
if polygons
else context.empty)
def unpack_regions(regions: Sequence[Contour],
context: Context) -> Union[Empty, Polygon, Multipolygon]:
polygon_cls = context.polygon_cls
return ((context.multipolygon_cls([polygon_cls(region, [])
for region in regions])
if len(regions) > 1
else polygon_cls(regions[0], []))
if regions
else context.empty)