def get_year_start(day=None):
    day = add_timezone(day or datetime.date.today())
    return day.replace(month=1).replace(day=1)
Test if memoization persists
dataset/ETHPy150Open caktus/django-timepiece/timepiece/utils/__init__.py/get_year_start--crossover with--dataset/ETHPy150Open duerrp/pyexperiment/tests/test_persistent_memoize.py/TestPersistentMemoize.test_persists