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A comment on Python Default Dict. Parent comment

Re:Python Default Dict by earthboundkid on Wednesday May 05, 2021 @02:30PM (#27053795)
Python has too many ways to do it:

    >>> state2name2visited = {}
    >>> state2name2visited.setdefault("PA", {}).setdefault("Joe", []).append("Pittsburgh")
    >>> state2name2visited
    {'PA': {'Joe': ['Pittsburgh']}}
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Re:Python Default Dict by abcxjeb284 on Sunday May 09, 2021 @02:14AM (#27093671)
It’s really 2 ways to do it, and the defaultdict way (I believe) would have less allocations in a deeply nested loop (since this version has to create a {} and a [] every time).

Also setdefault causes confusion for less experienced users in a way that the defaultdict format does not.

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