gistfile1.txt

 ~ @ pip-run pytz -- -q
>>> import pytz
>>> import datetime
>>> est = pytz.timezone('US/Eastern')
>>> datetime.datetime(2018, 3, 11, 9, 0, 0).replace(tzinfo=est) - datetime.datetime(2018, 3, 10, 9, 0, 0).replace(tzinfo=est)
datetime.timedelta(days=1)
>>> est.localize(datetime.datetime(2018, 3, 11, 9, 0, 0)) - est.localize(datetime.datetime(2018, 3, 10, 9, 0, 0))
datetime.timedelta(seconds=82800)