loop_regions.stack.reference

                local for: [0; 2; 2]
            non-local for: [0; 2; 0]
         local while body: [0; 2; 2]
      nonlocal while body: [0; 2; 0]
         local while cond: [0; 2; 2]
      nonlocal while cond: [0; 2; 0]