Write a python program that ask the user the year number. You need to check if this year is a leap year.

The rules in Gregorian calendar are as follows:

a year is a leap year if its number is exactly divisible by $4$ and is not exactly divisible by $100$

a year is always a leap year if its number is exactly divisible by $400$

Warning. The output should be as follows:

$2000$ is a leap year

$1700$ is a common year