[{'role': 'USR', 'utterance': 'May I help you?'}
 {'role': 'SYS', 'utterance': "Yes. I'm looking for a green dress."}
 {'role': 'USR', 'utterance': 'What size do you wear? These dresses are on sale.'}
 {'role': 'SYS', 'utterance': 'I wear size 32. This one looks nice. Where may I try it on?'}
 {'role': 'USR', 'utterance': "Come this way. Here's the dressing room."}
 {'role': 'SYS', 'utterance': 'How does it look?'}
 {'role': 'USR', 'utterance': "It looks nice. And it's not expensive."}]
{'role': 'SYS', 'utterance': 'How much is it?'}