Why does this python datetime format not convert the string of the same format into a datetime object successfully?

Question

import datetime as dt

time_str = '2022-02-25 18:37:46.594385+00:00'

Then I try to convert this into a datetime object as follows:

dt.datetime.strptime(time_str,'%Y-%m-%d %H:%M:%S.%f%z')

However it results in the following error:

ValueError: time data '2022-02-25 18:37:46.594385+00:00' does not match format '%Y-%m-%d %H:%M:%S.%f%z'

The error appears to be coming from the %z section of the format, but overall I do not understand why this is not working, since it seems the specified format does match the string format. If you could help identify any issues and suggest a solution to convert the example time_str into a datetime object successfully. Thanks!