datetime_tz.fromtimestamp has no optional tz parameter

[io41]

As a drop-in replacement for the std lib datetime module I was surprised that the datetime_tz.fromtimestamp method doesn't allow an optional tz parameter like it's standard library counterpart.

Was this an intentional omission?

[mithro]

I think it may have been an oversight, the tz parameter is however a little confusing. POSIX timestamps are always in UTC, which means the two are equivalent;

datetime_tz.fromtimestamp(ts, "US/Pacific")
# is identical to
datetime_tz.fromtimestamp(ts).astimezone("US/Pacific")

It will probably take me a while to fix the issue myself, I'd welcome patches though!