timeit-dictionary-accessors.py

from collections import defaultdict
import numpy
from timeit import timeit

DATA = {"value": 1}


def square_bracket():
    assert DATA["value"] is not None


def square_bracket_not_exists():
    value = "non_existent" in DATA and DATA["non_existent"] or None
    assert value is None


def get_method():
    assert DATA.get("value") is not None


def get_method_not_exists():
    assert DATA.get("non_existent") is None


def get_method_not_exists_with_default():
    assert DATA.get("non_existent", None) is None


def square_bracket_not_exists_try():
    try:
        assert DATA["non_existent"] is not None
    except KeyError:
        pass


RUNS = 5000
timing = defaultdict(list)
funcs_to_time = [
    square_bracket,
    square_bracket_not_exists,
    get_method,
    get_method_not_exists,
    get_method_not_exists_with_default,
    square_bracket_not_exists_try,
]
for _ in range(RUNS):
    for func in funcs_to_time:
        timing[func.__name__].append(timeit(func, number=RUNS))

for key, values in timing.items():
    print(
        f"{key},{numpy.mean(values)},{numpy.percentile(values, 90)},"
        f"{numpy.percentile(values,95)},{numpy.percentile(values,99)}"
    )

.get is about 18% slower than using the square bracket accessor. These runs were using python 3.10 on an M1 mac.