Python sets have these methods for all the standard relational algebra operations: s.union(t) s | t new set with elements from both s and t s.update(t) s |= t return set s with elements added from t s.intersection_update(t) s &= t return set s keeping only elements also found in t s.intersection(t) s & t new set with elements common to s and t What's the difference? I see that it says that the update() versions returns s instead of a new set, but if I write x = s.update(t), does that means that id(x) == id(s)? Are they references to the same object now? Why are both sets of methods implemented? It doesn't seem to add any significant functionality. Continue reading...
