firstweekday() & setfirstweekday() to get and set first week day of the calendar.

firstweekday() : Returns the value of first week day ( 0 to 6 ) of calendar. Monday is 0 and Sunday is 6
setfirstweekday() : Set the value for first week day of the calendar. ( takes value 0 to 6 )

In below calendar the first weekday is starting on Monday ( 0 ). This is the default first week day for the calendar.
Monday firstweekday() value is 0 , Tuesday is 1 ... and Sunday is 6.

import calendar
print(calendar.calendar(2020))


                               2020

      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  3  4  5                   1  2                      1
 6  7  8  9 10 11 12    3  4  5  6  7  8  9    2  3  4  5  6  7  8
13 14 15 16 17 18 19   10 11 12 13 14 15 16    9 10 11 12 13 14 15
20 21 22 23 24 25 26   17 18 19 20 21 22 23   16 17 18 19 20 21 22
27 28 29 30 31         24 25 26 27 28 29      23 24 25 26 27 28 29
                                              30 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  4  5                1  2  3    1  2  3  4  5  6  7
 6  7  8  9 10 11 12    4  5  6  7  8  9 10    8  9 10 11 12 13 14
13 14 15 16 17 18 19   11 12 13 14 15 16 17   15 16 17 18 19 20 21
20 21 22 23 24 25 26   18 19 20 21 22 23 24   22 23 24 25 26 27 28
27 28 29 30            25 26 27 28 29 30 31   29 30

        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  4  5                   1  2       1  2  3  4  5  6
 6  7  8  9 10 11 12    3  4  5  6  7  8  9    7  8  9 10 11 12 13
13 14 15 16 17 18 19   10 11 12 13 14 15 16   14 15 16 17 18 19 20
20 21 22 23 24 25 26   17 18 19 20 21 22 23   21 22 23 24 25 26 27
27 28 29 30 31         24 25 26 27 28 29 30   28 29 30
                       31

      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  3  4                      1       1  2  3  4  5  6
 5  6  7  8  9 10 11    2  3  4  5  6  7  8    7  8  9 10 11 12 13
12 13 14 15 16 17 18    9 10 11 12 13 14 15   14 15 16 17 18 19 20
19 20 21 22 23 24 25   16 17 18 19 20 21 22   21 22 23 24 25 26 27
26 27 28 29 30 31      23 24 25 26 27 28 29   28 29 30 31
                       30

To set the first week day in our calendar we can use setfirstweekday()
To read the first week day of our calendar we can use firstweekday(). Here is the code.

import calendar
calendar.setfirstweekday(3) # Thrusday is the first week day
print("First week day :",calendar.firstweekday())
print(calendar.calendar(2020))

First week day : 3
                               2020

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

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

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

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

We will display only monthly calendar. We already set the first week day to 3 ( Thrusday )

import calendar
print(calendar.month(2020,7, w=1, l=1))

     July 2020
Th Fr Sa Su Mo Tu We
                   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

We can change the first week day to Sunday

import calendar
calendar.setfirstweekday(6)
print(calendar.month(2020,7, w=1, l=1))

Output

     July 2020
Su Mo Tu We Th Fr Sa
          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

Calendar Module in Python

All String methods tuple Python- Tutorials

Subhendu Mohapatra

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calendar() first week day

Subhendu Mohapatra