Creating an empty list in Python

Question

What is the best way to create a new empty list in Python?
l = []
or
l = list()
I am asking this because of two reasons:​

1. Technical reasons, as to which is faster. (creating a class causes overhead?)​

2. Code readability - which one is the standard convention.

Answer 1

Here is how you can test which piece of code is faster:

% python -mtimeit "l=[]" 10000000 loops, best of 3: 0.0711 usec per loop % python -mtimeit "l=list()" 1000000 loops, best of 3: 0.297 usec per loop

However, in practice, this initialization is most likely an extremely small part of your program, so worrying about this is probably wrong-headed.

Readability is very subjective. I prefer [], but some very knowledgable people, like Alex Martelli, prefer list() because it is pronounceable.