b_getattr.py

import time

class F:
    def __getattr__(self, name):
        if name == 'spam':
            return 42


def foo(f):
    f.spam
    f.spam
    f.spam
    f.spam
    f.spam
    f.spam
    f.spam
    f.spam
    f.spam
    f.spam
    f.spam
    f.spam
    f.spam
    f.spam
    f.spam
    f.spam
    f.spam

def test():
    f = F()

    # warmup
    for _ in range(10000):
        foo(f)

    # bench
    st = time.monotonic()
    for _ in range(10**6):
        foo(f)
    print(time.monotonic() - st)

test()