Reference library

Dictionaries & sets

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

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Dictionaries & sets easy

How to Check if a Set is a Subset in Python

Check whether one set contains all elements of another set using the issubset method.

set subset membership
Python 
def is_subset(allowed_set, check_set):
    """
    Check if check_set is a subset of allowed_set.
    Returns True if all elements of check_set are in allowed_set, otherwise False.
    """
    return check_set.issubset(allowed_set)

if __name__ == "__main__":
    # Example usage
    allowed = {1, 2, 3, 4, 5}
    valid…
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