linearring - polygone

>>> poly1.exterior.wkt
'LINEARRING (1 2, 2 5, 6 5, 7 2, 5 1, 1 2)'
 
>>> poly1.boundary.wkt
'LINESTRING (1 2, 2 5, 6 5, 7 2, 5 1, 1 2)'
 
# prédicat unaire
>>> poly2.exterior.is_ring
True
>>> poly2.boundary.is_ring
False