Change the date_range function to return a list of all dates between start and end instead of return interval from datetime import datetime as dt from datetime import timedelta as td def date_range(start_date, end_date): lst = [] If start_date > end_date: return [] else: try: start = (dt.strptime(start_date, '%Y-%m-%d')) end = (dt.strptime(end_date, '%Y-%m-%d')) interval = end - start return interval except: return 'Incorrect date format' date_range('2022-12-01', '2022-12-20') Translated with www.DeepL.com/Translator (free version)

from datetime import datetime as dt
from datetime import timedelta as td
def date_range(start_date, end_date):
    lst = []
    if start_date > end_date:
        return []
    else:
        try:
            start = (dt.strptime(start_date, '%Y-%m-%d'))
            end = (dt.strptime(end_date, '%Y-%m-%d'))
            interval = end - start
            for i in range(interval.days + 1):
                lst.append(start.strftime('%Y-%m-%d'))
                start = start + td(days=1)
            return lst
        except:
            return 'Incorrect date format'

date_range('2022-12-01', '2022-12-20')