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Lesson 28. Aliasing and copying lists and dictionaries

After reading lesson 28, you’ll be able to

• Make aliases for mutable objects (lists and dictionaries)
• Make copies of mutable objects (lists and dictionaries)
• Make sorted copies of lists
• Remove elements from mutable objects based on certain criteria

Mutable objects are great to use because they allow you to modify the object itself without making a copy. When your mutable objects are large, this behavior makes sense because otherwise, making a copy of a large item every time you make a change to it is expensive and wasteful. But using mutable objects introduces a side effect that you need to be aware of: you can have more than one variable bound to the same mutable object, and the object ...