Reference library

Dictionaries & sets

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

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Dictionaries & sets easy

How to Set Nested Dict Value Creating Missing Keys in Python

Set a value deep inside a nested dictionary, automatically creating any missing intermediate dicts along the path.

dictionary nested mutation
Python 
def set_nested_value(d, keys, value):
    """
    Set a value in a nested dict, creating missing intermediate keys.
    
    Args:
        d: The dict to modify
        keys: Iterable of keys forming the path (e.g., ['a', 'b', 'c'])
        value: The value to set at the final key
    """
    current = d
    for key i…
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