def rpoplpush(self, src, dst):
with self.pipe as pipe:<EOL><INDENT>f = Future()<EOL>res = pipe.rpoplpush(self.redis_key(src), self.redis_key(dst))<EOL>def cb():<EOL><INDENT>f.set(self.valueparse.decode(res.result))<EOL><DEDENT>pipe.on_execute(cb)<EOL>return f<EOL><DEDENT>
RPOP a value off of the ``src`` list and atomically LPUSH it
on to the ``dst`` list.  Returns the value.