urllib2.py 文件源码

def __init__(self, proxies=None):
        if proxies is None:
            proxies = getproxies()
        assert hasattr(proxies, 'has_key'), "proxies must be a mapping"
        self.proxies = proxies
        for type, url in proxies.items():
            setattr(self, '%s_open' % type,
                    lambda r, proxy=url, type=type, meth=self.proxy_open: \
                    meth(r, proxy, type))