More compact way to get the difference between two datetime objects and then convert the difference into seconds is shown below (Python 3x):
from datetime import datetime
time1 = datetime.strftime('18 01 2021', '%d %m %Y')
time2 = datetime.strftime('19 01 2021', '%d %m %Y')
difference = time2 - time1
difference_in_seconds = difference.total_seconds()