SQL & PL/SQL

Database: 21c ATP Free Tier
I'm looking for the JSON version of this (LiveSQL PL/SQL code for converting cursor to XML)
So, if I give a cursor like:

open cur for
    select column_name, data_type
    from user_tab_cols
    where table_name = 'EMP';

The function should return JSON (or json_object_t) that matches something like:

{ "ROWSET":[
        { "COLUMN_NAME":"EMPNO", "DATA_TYPE":"NUMBER" },
        { "COLUMN_NAME":"DEPTNO", "DATA_TYPE":"NUMBER" },
        { "COLUMN_NAME":"HIRE_DATE", "DATA_TYPE":"DATE" },
        ...
    ]
}

Thanks,
MK