Find the Friday of previous/last week in python

Question

Eg1. Suppose I have a day 4/30/07 .Then I need to get 4/27/07.

Eg2. Suppose I have a day 6/29/07 .Then I need to get 6/22/07.

Answer 1

Assuming day is a datetime.date or datetime.datetime object, this code creates a datetime/date object for last week's friday:

friday = day - timedelta(days=day.weekday()) + timedelta(days=4, weeks=-1)

Explanation: timedelta(days=day.weekday()) is the offset between monday and day so adding 4 days and subtracting one week will get you last week's friday.

Of course you can simplify this (+4d -1w = -3d):

friday = day - timedelta(days=day.weekday() + 3)

Note: To get timedelta, use from datetime import timedelta or just import datetime and use datetime.timedelta