dialogue: THEM: gimme book and hat <eos> YOU: no <eos> THEM: gimme book hat and 2 balls <eos> YOU: no <eos> THEM: gimme book and 2 balls <eos> YOU: ok <eos> THEM: <selection>
output: item0=0 item1=1 item2=1 item0=1 item1=0 item2=2