Reference library

Dictionaries & sets

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

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Dictionaries & sets easy

How to Map Dictionary Values with a Transformation Function in Python

Create a reusable function that applies a transformation to every value in a dictionary and returns a new dict.

dictionaries mapping comprehension
Python 
def transform_dict_values(d, func):
    """Apply a transformation function to every value in a dictionary."""
    return {key: func(value) for key, value in d.items()}


if __name__ == "__main__":
    original = {"a": 1, "b": 2, "c": 3}
    doubled = transform_dict_values(original, lambda x: x * 2)
    print(doubled)
…
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