[Python-Dev] Status on PEP-431 Timezones

[Jon Ribbens]

On Mon, Jul 27, 2015 at 04:28:48PM -0700, Chris Barker wrote:
>      > The only other thing I found
>      > really weird about datetime is how Python 2 had no implementation of
>      > a UTC tzinfo class, despite this being utterly trivial -
> 
>    Huh? it is either so trivial that there is no point -- simiply say that
>    your datetimes are UTC, and you are done.
>    Or it's not the least bit trivial -- the only difference between a UTC
>    datetime and a "naive" datetime is that one can be converted to (or
>    interact with) other time zones. Except that, as we know from this
>    conversation, is very, very non-trivial!

No, it has nothing to do with conversions. The difference between a
naive timezone and a UTC one is that the UTC one explicitly specifies
that it's UTC and not "local time" or some other assumed or unknown
timezone. This can make a big difference when passing datetime
objects to third-party libraries, such as database interfaces.