Changing month_id when looping over dates in python

Question

I want to create a dictionary of dates where I have an id for each day, and a month id for each day in a specific month. Like:

id	month_id	date
1	1	2021-01-01
2	1	2021-01-02
3	1	2021-01-03
...	...	....
32	2	2021-02-01
33	2	2021-02-02

question from:https://stackoverflow.com/questions/65843941/changing-month-id-when-looping-over-dates-in-python

Answer 1

You need to keep track of the month and if it changes increase the month_id as below

def create_date_table():
    d1 = date(2021, 1, 1)
    d2 = date(2022, 12, 31)
    delta = d2 - d1
    dates = []
    date_id = 1
    month_id = 1
    last_month = d1.month
    for i in range(delta.days + 1):
        new_date = (d1 + timedelta(days=i))
        full_date = new_date.strftime('%Y-%m-%d')
        dates.append({'id': date_id,
                      'month_id': month_id,
                     'date': full_date})
        date_id+=1
        #increase the month_id here when month changes
        if last_month != new_date.month:
            last_month = new_date.month
            month_id+=1
    print(dates)