Python's id() function output in prompt and script mode

[stormshadow]

In CPython it is agreed that id's (in effect addresses) of objects with values > 256 should be different.

When using the Python prompt in a terminal this is exactly what happens. Doing the same by running a script with the same Python contents gives identical id's.

Python 3 Prompt

>>> a = 500
>>> b = 500
>>> print(id(a))
139745079475056
>>> print(id(b))
139745079475248

Script test.py
python3 /tmp/test.py
139835321420368
139835321420368

Can anyone shine some light on this please?