Django provides django.utils.timezone to make handling dates and times easier. Not every python project has access to django.utils.timezone. pytz is mostly what you need to get timezones right, but there's still room for something like this.
http://delorean.readthedocs.io
http://github.hubspot.com/sanetime/
https://github.com/zachwill/moment
https://docs.djangoproject.com/en/1.10/topics/i18n/timezones...
The most similar to this are Arrow and Delorean, maybe Django timezone if you use Django.