datetime addition

Leap
Leap in Python 
import datetime


def leap_year(year):
    return (datetime.datetime(year, 2, 28)
            + datetime.timedelta(days=1)).day == 29
Caution

This approach may be considered a "cheat" for this exercise, which is intended to practice Boolean operators and logic. It also adds a tremendous amount of overhead in both performance and memory, as it imports all of the datetime module and requires the instantiation of both a datetime object and a datetime.timedelta object.

For more information, see this exercises performance article.

By adding a day to February 28th for a given year, you can see if the new day falls on the 29th of February, or the 1st of March. If it is February 29th, then the function returns True for the year being a leap year.

  • A new datetime object is created for February 28th of the year.
  • Then the timedelta of one day is added to that datetime, and the function returns if the day property of the resulting datetime object is the 29th.
4th Dec 2024 · Found it useful?

Other Approaches to Leap in Python

Other ways our community solved this exercise
def leap_year(year):
    return year % 4 == 0 and (year % 100 != 0 or year % 400 == 0)
Boolean chain

Use a chain of boolean expressions. 

def leap_year(year):
    return not year % 400 if not year % 100 else not year % 4
Ternary operator

Use a ternary operator of boolean expressions. 

from calendar import isleap

def leap_year(year):
    return isleap(year)
calendar.isleap() function

Use the calendar module.