Reference library

Dictionaries & sets

Key–value maps, uniqueness, counting, grouping, and fast lookups.

1 match
Dictionaries & sets medium

How to Build a Two-Way Dictionary in Python

Implement a BiDict class that supports both forward key-to-value and reverse value-to-key lookups with a simple add, delete, and update API.

dictionary bidirectional class
Python 
class BiDict:
    def __init__(self, data=None):
        self.forward = {}
        self.backward = {}
        if data:
            self.update(data)

    def update(self, data):
        for key, value in data.items():
            self[key] = value

    def __setitem__(self, key, value):
        self.forward[key] = val…
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