Handling time zones is a pretty messy affair overall, but language runtimes may
have even bigger problems. As a recent discussion on the Python discussion
forum shows, there are considerations beyond those that an operating
system or distribution needs to handle. Adding support for the IANA time zone
database to the Python standard library, which would allow using names
like “America/Mazatlan” to designate time zones, is more complicated than
one might think—especially for a language trying to support multiple platforms.

Source: LWN.net – [$] Python time-zone handling