

def _find_groups(self):
    "Returns a tuple (reverse string, group count) for a url.\n\n        For example: Given the url pattern /([0-9]{4})/([a-z-]+)/, this method\n        would return ('/%s/%s/', 2).\n        "
    pattern = self.regex.pattern
    if pattern.startswith('^'):
        pattern = pattern[1:]
    if pattern.endswith('$'):
        pattern = pattern[:(- 1)]
    if (self.regex.groups != pattern.count('(')):
        return (None, None)
    pieces = []
    for fragment in pattern.split('('):
        if (')' in fragment):
            paren_loc = fragment.index(')')
            if (paren_loc >= 0):
                pieces.append(('%s' + fragment[(paren_loc + 1):]))
        else:
            pieces.append(fragment)
    return (''.join(pieces), self.regex.groups)

dataset/ETHPy150Open RobotWebTools/rosbridge_suite/rosbridge_server/src/tornado/web.py URLSpec._find_groups/original