# Use frozensets as dictionary keys

Canonical URL: <https://datadriven.io/problems/use-frozensets-as-dictionary-keys-create-a-dict-that-maps-f-473a4ae5>

Domain: Python · Difficulty: medium

## Problem

Use frozensets as dictionary keys. Create a dict that maps frozenset({'a', 'b'}) to 'pair_ab' and frozenset({'c', 'd'}) to 'pair_cd'. Look up the key frozenset({'b', 'a'}) and print the result.

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