Skip Montanaro:

The robotparser.py module currently lives in Tools/webchecker.  In
preparation for its migration to Lib, I made the following changes:

    * renamed the test() function _test
    * corrected the URLs in _test() so they refer to actual documents
    * added an "if __name__ == '__main__'" catcher to invoke _test()
      when run as a main program
    * added doc strings for the two main methods, parse and can_fetch
    * replaced usage of regsub and regex with corresponding re code