What is calendar module in python?

The calendar module in Python provides functions to display calendars and perform calendar-related operations. By default, these calendars have Monday as the first day of the week and Sunday as the last.

Display the Calendar of an Year

To display the calendar of an year, use the calendar() method and set year as the parameter ?

import calendar

# Set the year
year = 2022

# Display the calendar
print(calendar.calendar(year))

The output of the above code is ?

                                  2022

      January                   February                   March
Mo Tu We Th Fr Sa Su      Mo Tu We Th Fr Sa Su      Mo Tu We Th Fr Sa Su
                1  2          1  2  3  4  5  6          1  2  3  4  5  6
 3  4  5  6  7  8  9       7  8  9 10 11 12 13       7  8  9 10 11 12 13
10 11 12 13 14 15 16      14 15 16 17 18 19 20      14 15 16 17 18 19 20
17 18 19 20 21 22 23      21 22 23 24 25 26 27      21 22 23 24 25 26 27
24 25 26 27 28 29 30      28                        28 29 30 31
31

       April                      May                       June
Mo Tu We Th Fr Sa Su      Mo Tu We Th Fr Sa Su      Mo Tu We Th Fr Sa Su
             1  2  3                         1             1  2  3  4  5
 4  5  6  7  8  9 10       2  3  4  5  6  7  8       6  7  8  9 10 11 12
11 12 13 14 15 16 17       9 10 11 12 13 14 15      13 14 15 16 17 18 19
18 19 20 21 22 23 24      16 17 18 19 20 21 22      20 21 22 23 24 25 26
25 26 27 28 29 30         23 24 25 26 27 28 29      27 28 29 30
                          30 31

        July                     August                  September
Mo Tu We Th Fr Sa Su      Mo Tu We Th Fr Sa Su      Mo Tu We Th Fr Sa Su
             1  2  3       1  2  3  4  5  6  7                1  2  3  4
 4  5  6  7  8  9 10       8  9 10 11 12 13 14       5  6  7  8  9 10 11
11 12 13 14 15 16 17      15 16 17 18 19 20 21      12 13 14 15 16 17 18
18 19 20 21 22 23 24      22 23 24 25 26 27 28      19 20 21 22 23 24 25
25 26 27 28 29 30 31      29 30 31                  26 27 28 29 30

      October                   November                  December
Mo Tu We Th Fr Sa Su      Mo Tu We Th Fr Sa Su      Mo Tu We Th Fr Sa Su
                1  2          1  2  3  4  5  6                1  2  3  4
 3  4  5  6  7  8  9       7  8  9 10 11 12 13       5  6  7  8  9 10 11
10 11 12 13 14 15 16      14 15 16 17 18 19 20      12 13 14 15 16 17 18
17 18 19 20 21 22 23      21 22 23 24 25 26 27      19 20 21 22 23 24 25
24 25 26 27 28 29 30      28 29 30                  26 27 28 29 30 31
31

Display a Specific Month

To display a specific month of a calendar, use the month() method with year and month as parameters ?

import calendar

# Display August 2022
print(calendar.month(2022, 8))

The output of the above code is ?

    August 2022
Mo Tu We Th Fr Sa Su
 1  2  3  4  5  6  7
 8  9 10 11 12 13 14
15 16 17 18 19 20 21
22 23 24 25 26 27 28
29 30 31

Get Weekday Numbers

The calendar module provides constants for weekday numbers, where Monday is 0 and Sunday is 6 ?

import calendar

print(f'Monday Weekday Number: {calendar.MONDAY}')
print(f'Tuesday Weekday Number: {calendar.TUESDAY}')
print(f'Wednesday Weekday Number: {calendar.WEDNESDAY}')
print(f'Thursday Weekday Number: {calendar.THURSDAY}')
print(f'Friday Weekday Number: {calendar.FRIDAY}')
print(f'Saturday Weekday Number: {calendar.SATURDAY}')
print(f'Sunday Weekday Number: {calendar.SUNDAY}')

The output of the above code is ?

Monday Weekday Number: 0
Tuesday Weekday Number: 1
Wednesday Weekday Number: 2
Thursday Weekday Number: 3
Friday Weekday Number: 4
Saturday Weekday Number: 5
Sunday Weekday Number: 6

Check if a Year is a Leap Year

To check if a year is a leap year, use the isleap() method. It returns True for leap years and False otherwise ?

import calendar

# Check if any of the years is a leap year
print(calendar.isleap(2020))
print(calendar.isleap(2021))
print(calendar.isleap(2022))
print(calendar.isleap(2023))
print(calendar.isleap(2024))
print(calendar.isleap(2025))

The output of the above code is ?

True
False
False
False
True
False

Get Day of the Week for a Date

Use weekday() to find which day of the week a specific date falls on ?

import calendar

# Get day of week for January 1, 2024 (Monday = 0)
day = calendar.weekday(2024, 1, 1)
print(f'January 1, 2024 is weekday: {day}')

# Get month calendar with specific first day
print(calendar.monthcalendar(2024, 1))

The output of the above code is ?

January 1, 2024 is weekday: 0
[[1, 2, 3, 4, 5, 6, 7], [8, 9, 10, 11, 12, 13, 14], [15, 16, 17, 18, 19, 20, 21], [22, 23, 24, 25, 26, 27, 28], [29, 30, 31, 0, 0, 0, 0]]

Conclusion

The calendar module provides essential functions for calendar operations including displaying full-year or monthly calendars, checking leap years, and determining weekdays for specific dates. These utilities are particularly useful for date-related applications and scheduling systems.