The python dateutil module provides powerful extensions to the standard
Computing of relative deltas (next month, next year, next monday,
last week of month, etc.)
Computing of relative deltas between two given dates and/or
Computing of dates based on very flexible recurrence rules, using
a superset of the iCalendar specification. Parsing of RFC strings
is supported as well.
Generic parsing of dates in almost any string format.
Timezone (tzinfo) implementations for tzfile(5) format files
(/etc/localtime, /usr/share/zoneinfo, etc.), TZ environment
string (in all known formats), iCalendar format files, given
ranges (with help from relative deltas), local machine timezone,
fixed offset timezone, UTC timezone, and Windows registry-based
Internal up-to-date world timezone information based on Olson's
Computing of Easter Sunday dates for any given year, using Western,
Orthodox or Julian algorithms.