Is it a leap year?

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In 1582 the Gregorian calendar was introduced. Our planet takes approximately 365.25 days to orbit the sun once. It's that .25 that creates the need for a leap year every four years. During non-leap years (common years) the calendar doesn't take into account the extra quarter of a day required by Earth to complete a single orbit. In leap years there are 29 days in February instead of 28.

Make

Write a program to say whether the year entered by a user is a leap year or not. Any year exactly divisible by four is usually a leap year unless it is also divisible by one hundred. The exception is that all years divisible by four hundred are always leap years.

Success Criteria

Remember to add a comment before a subprogram, selection or iteration statement to explain its purpose.

Complete the subprogram called is_leap_year that:

1. Returns True if the year is a leap year or False if it is not.
2. If the year is exactly divisible by four it is a leap year…
3. …unless it is divisible by one hundred in which case it is not a leap year…
4. …although any year that is divisible by four hundred is a leap year.

Complete the main program so that:

1. The user can input a year.
2. It outputs whether the year is a leap year or not.

Typical inputs and outputs from the program would be:

Enter a year: 1900
1900 is not a leap year.

Enter a year: 2000
2000 is a leap year.

Enter a year: 2022
2022 is not a leap year.

Enter a year: 2024
2024 is a leap year.

# Leap year program

# -------------------------
# Subprograms
# -------------------------
# Function to return if a year is a leap year
def is_leap_year(year):
---
    leap_year = False
---
    # If the year is divisible by 4 it is a leap year...
---
    if year % 4 == 0:
---
        leap_year = True
---
        # ...however, if it is also divisible by 100 it is not a leap year
---
        if year % 100 == 0:
---
            # ...but if it is divisible by 400 then it is a leap year
---
            if year % 400 == 0:
---
                leap_year = True
---
            # All other years are not leap years
---
            else:
---
                leap_year = False
---
        else:
---
            leap_year = True
---
    else:
---
        leap_year = False
---
    return leap_year
---


# -------------------------
# Main program
# -------------------------
---
year = int(input("Enter a year: "))
---
if is_leap_year(year):
---
    print(year, "is a leap year.")
---
else:
---
    print(year, "is not a leap year.")