Python's collections Module: Beyond defaultdict and Counter — 4 Hidden Gems That Solve Real Problems
Every Python developer knows defaultdict and Counter. They're the first things you reach for when you need to group items or count occurrences. But the collections module has more to offer — and these less-known tools can dramatically simplify your code.
Here's the thing: I used to write a lot of boilerplate for things like tracking configuration scopes, building lightweight data containers, or implementing sliding window algorithms. Then I actually read the collections docs beyond the first two entries. Here's what I found.
1. ChainMap — When You Need Multiple Dicts as One
The problem: You have layered configuration — default settings, environment overrides, user preferences, command-line args. You want to check each layer in order without merging them manually.
