I have tried using this but the output is not as desired

m = []
import calendar
for i in range(1, 13):m.append(calendar.month_name)
print(m)

Output: [<calendar._localized_month object at 0x7f901a7013d0>, <calendar._localized_month object at 0x7f901a7013d0>, <calendar._localized_month object at 0x7f901a7013d0>, <calendar._localized_month object at 0x7f901a7013d0>, <calendar._localized_month object at 0x7f901a7013d0>, <calendar._localized_month object at 0x7f901a7013d0>, <calendar._localized_month object at 0x7f901a7013d0>, <calendar._localized_month object at 0x7f901a7013d0>, <calendar._localized_month object at 0x7f901a7013d0>, <calendar._localized_month object at 0x7f901a7013d0>, <calendar._localized_month object at 0x7f901a7013d0>, <calendar._localized_month object at 0x7f901a7013d0>]

The month_name element acts like a list.

You can either subscript it:

>>> calendar.month_name[3]
'March'

Or use list on it:

>>> import calendar
>>> list(calendar.month_name)
['', 'January', 'February', 'March', 'April', 'May', 'June', 'July', 'August', 'September', 'October', 'November', 'December']

Note the blank at index 0. There is no month zero...

Which leads to the other issue in your code. If you correct your code to be:

import calendar
m=[calendar.month_name[i] for i in range(1,13)]
# or
m=calendar.month_name[1:]

In either case you now have turned 'January' into element 0 instead of element 1. You will need to covert every date.