[Zope] date format in other time-zone

[Sin Hang Kin]

Is it possible to format a date to GMT or in general in other timezone other
zone?

I have read through the Quick reference but do not have answer. The
ToZone(z) is listed there under DateTime. But How can I use that?

Moreover, how can I make date-time calculate : adding 3 days to current
time. Add 2 minutes to current time, etc.

Rgs,

Kent Sin