days in month function python

1def leap_year(year):
2    if year % 400 == 0:
3        return True
4    if year % 100 == 0:
5        return False
6    if year % 4 == 0:
7        return True
8    return False
9
10def days_in_month(month, year):
11    if month in {1, 3, 5, 7, 8, 10, 12}:
12        return 31
13    if month == 2:
14        if leap_year(year):
15            return 29
16        return 28
17    return 30
18
19print(days_in_month(2, 2016))  # 29
20

1>>> p = pd.Period('2018-2-17')
2>>> p.days_in_month
328
4