oracle sql function : get columns name of table

create or replace function get_columns_name(tab_name VARCHAR2) return VARCHAR2 is
   val VARCHAR2(3200);
   
begin
  for col in (Select COLUMN_NAME from user_tab_columns where table_name = tab_name) loop
    val := val || ',' || col.column_name;
  end loop;
  
  return substr(val, 2);
end;

example

set serveroutput on
begin
    dbms_output.put_line ('tb_user --> ' || get_columns_name('tb_user'));
    -- tb_user --> id,name,username,password,version
end;