Have a look at the sample XOG prj_timeperiods_write.xml.
But, given that the Base Calendar is marked as 'non-working day', and the UI prevents user from submitting hours on 'non-working days', the XOG may not be able to undertake either.
Unclear what you are trying to achieve, as if you then mark what I assume are 'public holidays' as working day to record as PTO (which I assume is personal time off), then this will impact on all your schedules. Don;t need an answer on this one, just a warning on what may occur as a result.