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Python Immutable Data Types

Posted by Roger Perelló
Roger Perelló
4,293 Points

Why {False, True}?

Hi everyone!

I'd like to know why {True, False} gives {False, True} when printed every time, without changing order. Also, why {False, True} instead of {True, False}?

I've noticed that if I print {None, True, False} it then gives {None, True, False} instead of {None, False, True}. What is this madness? Thank you for your help.

2 Answers

Steven Parker
Steven Parker
231,007 Points
Steven Parker
Steven Parker
231,007 Points

In Python, a set is an unordered collection, which means that the order of elements in a set is undefined. While sets are iterable, they do not support indexing, slicing, sorting, or other sequence-like behavior. The order that you see when listing the entire set is simply a result of the optimization algorithms in the engine implementation.

A Python engine on a different platform, or a different version, might list the same set in a different order.

Roger Perelló
Roger Perelló
4,293 Points
Roger Perelló
Roger Perelló
4,293 Points

Thanks!