Quick demo of dealing with timestamps and timezones, which suck.

timezones_suck.py

from calendar import timegm
import datetime

from django.utils.timezone import make_aware
import pytz

# Roundtrip a datetime to a timestamp (epoch, seconds) and back again
date = datetime.datetime(2015, 10, 25, 2)
timestamp = timegm(date.timetuple()) 
>>> 1445738400

# For a sanity check of epoch timestamps I used online converters like
# http://www.epochconverter.com/

# Use utcfromtimestamp rather than fromtimestamp
# This gives you a naive time but doesn't move it from UTC
datetime.datetime.utcfromtimestamp(timestamp)
>>> datetime.datetime(2015, 10, 25, 2, 0)

# If you use fromtimestamp you get a localized time instead
datetime.datetime.fromtimestamp(timestamp)
>>> datetime.datetime(2015, 10, 25, 3, 0)

# Additionally, if you call django's make_aware on a naive datetime at the DST
# transition, it will barf an AmbiguousTimeError (as it should)
make_aware(date)
>>> barf AmbiguousTimeError

# Solution is to set the timezone when you call make_aware
make_aware(date, timezone=pytz.UTC)
>>> datetime.datetime(2015, 10, 25, 2, 0, tzinfo=<UTC>)

# If a timestamp is received and assumed UTC and what we want is a timezone-aware
# datetime also in UTC, this works:
make_aware(dt.datetime.utcfromtimestamp(timestamp), timezone=pytz.UTC)