Cannot create perlplu function
Due to plperlu being untrusted, the account requires superuser authorization:

DROP LANGUAGE plperl;
DROP LANGUAGE plperlu;
CREATE OR REPLACE TRUSTED LANGUAGE plperlu;
UPDATE pg_language set lanpltrusted = true where lanname='plperlu';
GRANT ALL ON LANGUAGE plperlu TO account_name WITH GRANT OPTION;
ALTER USER account_name WITH SUPERUSER;


I do not know if plperl and plperlu are allowed to be installed at the same time, so I dropped the former. The function can now be created.