Why do Python's datetime.strftime('%w') and datetime.weekday() use different indexes for the days of the week?

Question

In Python, showing the day of the week as an integer using datetime.strftime() shows a different result than using datetime.weekday().

Answer 1

Originally, the ISO 8601 standard used 1 .. 7 to represent Monday through Sunday. For convenience, later on the interpretation 0=Sunday was permitted.

If you want to use something that is more consistent, try using isoweekday

The 0=Monday standard is the European convention. I guess that's no surprise :P