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What is the difference between a list and a set in Python?

The main differences between lists and sets in Python are:

Lists are ordered sequences of elements, whereas sets are unordered collections of unique elements.

Lists allow duplicates, whereas sets do not. In sets, each element must be unique.

Lists are mutable, which means you can add, remove, or modify elements after the list has been created. Sets are also mutable. On the other hand, tuples are immutable, which means that once a tuple has been created, its elements cannot be changed.

Lists are indexed, meaning you can access individual elements using an index number. Sets are not indexed.

Lists are implemented as arrays, which means that accessing elements by index is an O(1) operation. On the other hand, sets use hash tables, which means that lookups are O(1) on average, but O(n) in the worst case.

Lists have many built-in methods for adding, removing, and manipulating elements, whereas sets have fewer methods but are optimized for checking if an element is in the set and removing duplicates.

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