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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 handle(cls, vm, args):
 """ Setup forwarding connection to given VM and pipe docker cmds over SSH. """

        docker = Iaas.info(vm)
        if not docker:
            raise Exception('docker vm %s not found' % vm)

        if docker['state'] != 'running':
            Iaas.start(vm)

        # XXX
        remote_addr = docker['ifaces'][0]['ips'][0]['ip']

        port = unixpipe.setup(remote_addr, 'root', '/var/run/docker.sock')

        os.environ['DOCKER_HOST'] = 'tcp://localhost:%d' % port
        cls.echo('using DOCKER_HOST=%s' % os.environ['DOCKER_HOST'])

        subprocess.call(['docker'] + list(args))