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Algorithms & data structures easy

How to Remove Duplicates in Python Preserving Order

Removes duplicate items from a list while keeping the first occurrence order intact using a set for fast membership checks.

deduplication set list
Python 
def remove_duplicates_preserving_order(items):
    seen = set()
    result = []
    for item in items:
        if item not in seen:
            seen.add(item)
            result.append(item)
    return result

if __name__ == "__main__":
    sample = [3, 1, 2, 1, 3, 4, 2, 5]
    unique_items = remove_duplicates_preserv…
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