It meanse one of the datetime instance contains timezone info, while the others doens't.
import datetimed1 = datetime.datetime.now(datetime.timezone.utc) # datetime.datetime(2021, 2, 24, 4, 30, 6, 598645, tzinfo=datetime.timezone.utc)d2 = datetime.datetime.utcnow() # datetime.datetime(2021, 2, 24, 4, 30, 14, 29200)diff = d2 - d1 # TypeError: can't subtract offset-naive and offset-aware datetimYou can either remove timzeone info
diff = d2 - d1.replace(tzinfo=None) Or add timezone info
diff = d2.replace(tzinfo=datetime.timezone.utc) - d1