>>> import dis
>>> index = compile("container['a']", "<example>", "eval")
>>> call = compile("container[ord('a')]", "<example>", "eval")
>>> dis.dis(index)
  1           0 LOAD_NAME                0 (container)
              3 LOAD_CONST               0 ('a')
              6 BINARY_SUBSCR
              7 RETURN_VALUE
>>> dis.dis(call)
  1           0 LOAD_NAME                0 (container)
              3 LOAD_NAME                1 (ord)
              6 LOAD_CONST               0 ('a')
              9 CALL_FUNCTION            1
             12 BINARY_SUBSCR
             13 RETURN_VALUE