#!/usr/bin/env python
# -*- coding: iso-8859-1 -*-

import re

# * significa cero o mas.
# \D* cero o mas caracteres que no son numeros.

p = re.compile(r"^\D*(\d{3})\D*(\d{3})\D*(\d+)$")
s = p.search("(555)6667777")
r = p.search("555.666 ext x7777")
print s.groups()
print r.groups()