Python: add models for `stdlib`

[yoff]

trafficstars

• urllib.parse.urljoin
• fnmatch.filter
• optparse.parse_args

This brings the number of results for py/shell-command-constructed-from-input on a database for tanghaibao/jvci extracted without the standard lib up from 5978 to 17055. With the standard library, we get 17062 results.