It seems pychecker is incorrect with its checks: please refer to http://bugs.python.org/issue25965
$ pychecker testcase.py
Processing module testcase (testcase.py)...
Warnings...
[system path]/optparse.py:1191: Function (init) has too many arguments (11)
[system path]/optparse.py:1400: Local variable (stop) not used
[system path]/optparse.py:1668: (file) shadows builtin
$ pychecker --version
0.8.19
$
Sorry, wrong URL: http://bugs.python.org/issue25964