euler19.py

from datetime import date, timedelta
from calendar import SUNDAY

def main():
    day = timedelta(days=1)
    start = date(1901, 1, 1)
    end = date(2000, 12, 31)

    total = 0
    while start < end:
        if (start.day == 1) and (start.weekday() == SUNDAY):
            total += 1
        start += day
    print(total)

if __name__ == "__main__":
    main()