benchmark return self

scratch.py

import timeit

setup_code = """\
class TestClass1:
    __slots__ = ("inner",)
    def __init__(self):
        self.inner = dict()

    def add(self, item):
        self.inner[item] = 1

    def remove(self, item):
        del self.inner[item]

t1 = TestClass1()

class TestClass2:
    __slots__ = ("inner",)
    def __init__(self):
        self.inner = dict()

    def add(self, item):
        self.inner[item] = 1
        return self

    def remove(self, item):
        del self.inner[item]
        return self
    
t2 = TestClass2()
"""
test1 = """\
for i in range(1000,4000,2):
    t1.add(i)
for i in range(1000,4000,2):
    t1.remove(i)
"""
test2 = """\
for i in range(1000,4000,2):
    t2.add(i)
for i in range(1000,4000,2):
    t2.remove(i)
"""
n = 10000
res1 = timeit.timeit(test1, setup=setup_code, number=n)
res2 = timeit.timeit(test2, setup=setup_code, number=n)
print(res1/n)
print(res2/n)