Test for membership should be 'not in' FLK-E713
Anti-pattern
Major
a year ago
—
a year old
No results found
That’s all we can say right now.
Description
Tests for membership should use the form x not in the_list rather than not x in the_list. The former example is simply more readable.
Bad practice
if not x in authors:
authors.append(x)
Recommended
if x not in authors:
authors.append(x)