Answer
Duplicate removal must state whether original order should be preserved. • dict.fromkeys preserves first-seen order for hashable values. • A set removes duplicates but should not be used when list order matters. • Unhashable values require another comparison strategy.
💡 Simple Example
values = [3, 1, 3, 2, 1]
unique = list(dict.fromkeys(values))
print(unique)
Output
[3, 1, 2]
⚡ Quick Revision
dict.fromkeys removes duplicate hashable items while preserving first-seen order.