Get seconds since midnight in Python [closed]

It is better to make a single call to a function that returns the current date/time:

from datetime import datetime

now = datetime.now()
seconds_since_midnight = (now - now.replace(hour=0, minute=0, second=0, microsecond=0)).total_seconds()

Or does

datetime.now() - datetime.now()

return zero timedelta for anyone here?