python datetime time range
import datetime
ndays = 4
now = datetime.datetime.today()
date_list = [now - datetime.timedelta(days=x) for x in range(ndays)]
date_list
>>> [datetime.datetime(2021, 8, 6, 10, 5, 32, 676787), datetime.datetime(2021, 8, 5, 10, 5, 32, 676787), datetime.datetime(2021, 8, 4, 10, 5, 32, 676787), datetime.datetime(2021, 8, 3, 10, 5, 32, 676787)]
# or
import pandas as pd
import datetime
datelist = pd.date_range(datetime.datetime.today(), periods=ndays)
datelist
>>> [Timestamp('2021-08-06 10:10:47.721405', freq='D'), Timestamp('2021-08-07 10:10:47.721405', freq='D'), Timestamp('2021-08-08 10:10:47.721405', freq='D'), Timestamp('2021-08-09 10:10:47.721405', freq='D')]