bug#10295: 24.0.92; Python completion fails on OSX (10.6.8)

[Leo]

1. emacs -q
2. M-x python-mode
3. C-c C-z
4. M-: (python-symbol-completions "s")

repeat step 4 a few times and you should notice the following
alternating results:

("setdefault" "sys")
nil
("setdefault" "sys")
nil
......

I wonder if this can be fixed before releasing emacs 24.1.

Tested on GNU Emacs 24.0.92.1 (i386-apple-darwin10.8.0, X toolkit) of 2011-12-14

I cannot reproduce this on a GNU/Linux host.

Regards,
Leo