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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _proxy_addr(self):
 """ Return proxy address to connect to as tuple object """

        proxy_type, proxy_addr, proxy_port, rdns, username, password = self.proxy
        proxy_port = proxy_port or DEFAULT_PORTS.get(proxy_type)
        if not proxy_port:
            raise GeneralProxyError("Invalid proxy type")
        return proxy_addr, proxy_port