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List literal

Sourcery refactoring id: list-literal

Description:

Replaces lists created with list() with []

Before:

x = list()

After:

x = []

Explanation:

The most concise and Pythonic way to create a list is to use the [] notation.

This fits in with the way we create lists with elements, saving a bit of mental energy that might be taken up with thinking about two different ways of creating lists.

x = ['first', 'second']

Doing things this way has the added advantage of being a nice little performance improvement.

Here are the timings before and after the change:

$ python3 -m timeit "x = list()"
5000000 loops, best of 5: 63.3 nsec per loop

$ python3 -m timeit "x = []"
20000000 loops, best of 5: 15.8 nsec per loop
Similar reasoning and performance results hold for replacing dict() with {}.

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