2236 

  2236 

  2237     @util.propertycache

  2237     @util.propertycache

  2238     def __contains__(self):

  2238     def __contains__(self):

  2239         return self.set().__contains__

  2239         return self.set().__contains__

  2240 

  2240 

  2241     def __sub__(self, other):

  2244     def __sub__(self, other):

  2242         """Returns a new object with the substraction of the two collections.

  2245         """Returns a new object with the substraction of the two collections.

  2243 

  2246 

  2244         This is part of the mandatory API for smartset."""

  2247         This is part of the mandatory API for smartset."""

  2245         # If we are operating on 2 baseset, do the computation now since all

  2248         # If we are operating on 2 baseset, do the computation now since all