unnecessary-dunder-call / C2801

Message emitted:

Unnecessarily calls dunder method %s. %s.

Description:

Used when a dunder method is manually called instead of using the corresponding function/method/operator.

Problematic code:

three = (3.0).__str__()  # [unnecessary-dunder-call]
twelve = "1".__add__("2")  # [unnecessary-dunder-call]


def is_bigger_than_two(x):
    return x.__gt__(2)  # [unnecessary-dunder-call]

Correct code:

three = str(3.0)
twelve = "1" + "2"


def is_bigger_than_two(x):
    return x > 2

Created by the unnecessary-dunder-call checker.