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Python

Tricia Cruz
Tricia Cruz
915 Points
Posted by Tricia Cruz
Tricia Cruz
915 Points

Why do we use append and extend for lists?

This is probably a silly question, but I just wanted to know why we use append and extend, rather than just going back to the list in your code and editing the elements directly?

1 Answer

Steven Parker
Steven Parker
231,236 Points
Steven Parker
Steven Parker
231,236 Points

If the elements are known in advance (at programming time), you would indeed just add them as additional literal list items. But in many cases, a program will build one or more lists as it runs, using data acquired at that later time.

The primary use of the list-expanding dynamic methods are for creating and maintaining those lists during the program execution.