Create queries to reset postgres database owners (excluding protected schemas/tables).

reassign_owner.sql

SELECT 'ALTER TABLE '|| schemaname || '.' || tablename ||' OWNER TO username;'
FROM pg_tables WHERE NOT schemaname IN ('pg_catalog', 'information_schema')
ORDER BY schemaname, tablename;

SELECT 'ALTER SEQUENCE '|| sequence_schema || '.' || sequence_name ||' OWNER TO username;'
FROM information_schema.sequences WHERE NOT sequence_schema IN ('pg_catalog', 'information_schema')
ORDER BY sequence_schema, sequence_name;

SELECT 'ALTER VIEW '|| table_schema || '.' || table_name ||' OWNER TO username;'
FROM information_schema.views WHERE NOT table_schema IN ('pg_catalog', 'information_schema')
ORDER BY table_schema, table_name;