'Replace the JUNK(x) variable with random alphanum.'

def _replace_JUNK(self, query):

    match_obj = self._junk_re.search(query)
    if (match_obj is not None):
        if match_obj.group(1).isdigit():
            length = int(match_obj.group(1))
            query = self._junk_re.sub(rand_alnum(length), query)
    return query
