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Jacob Brookhart
Courses Plus Student 6,765 Pointspres = pres or set()
So another newbie question... in this code challenge, the function is already populated with pres = pres or set. The default condition of pres = None. So why is it that this code selects an empty set (set()) instead of an empty variable? How is this hierarchy organized?
1 Answer
Steven Parker
231,248 PointsThe value "None" is considered "falsey". So when "pres" is "None", then the code "pres = pres or set()" works the same as if it were just "pres = set()".
Jacob Brookhart
Courses Plus Student 6,765 PointsJacob Brookhart
Courses Plus Student 6,765 PointsAny recommendation on where to find the documentation for this? It makes sense but I think I need to go into the semantics of it
Steven Parker
231,248 PointsSteven Parker
231,248 PointsYou might look in the official Python documentation on Truth Value Testing and Boolean Operations.
Jacob Brookhart
Courses Plus Student 6,765 PointsJacob Brookhart
Courses Plus Student 6,765 PointsThank you!