where table privileges are stored

Hello,

I need to check in a GUI if a user has certain privileges on the table he is trying to modify - insert/update/delete.
Something I could query system catalogs about:
Select ... from ... where table_name = 'MYTABLE';

Does Postgres store user privileges on tables in format similar to the one below, I mean the info below to be stored as a text field somewhere?
grant delete on MYTABLE to myuser
grant insert on MYTABLE to myuser

Thanks,
Nina

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Nina Markova,
Database Analyst / Analyst de base de données
email/courriel: nmarkova(at)nrcan(dot)gc(dot)ca

Infrastructure & Development Group / Groupe de l'infrastructure et du developpement
Canadian Hazards Information Service / Service canadien d'informations sur les risques
Earth Sciences Sector / Secteur des sciences de la Terre
Natural Resources Canada / Ressources naturelles Canada

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