How can I set the flexfield context and values of a hz_locations object using Groovy, REST, or SOAP?

Hello all,

we use the ATTRIBUTE_CATEGORY column in the HZ_LOCATIONS table to discern between "Home addresses" and "P.O. box addresses".

We use this for both Account and Contact PartySites.

For example, see the right hand side for a query result for query:

select hz_locations.* from hz_party_sites
inner join hz_locations on hz_party_sites.location_id = hz_locations.location_id
where party_site_id = 300000024399623;

Note that we have ATTRIBUTE_CATEGORY = 'P.O. Box address' and have two flexfield segments,
for which ATTRIBUTE2 = '4434' is the postbox number.

What I would like to do, is create an Account or Contact address (PartySite + Location objects) programmatically from within an Application Composer Groovy script.