nltk中如何提取NP(名词短语)?

Question

例如：
A novel device was designed to measure drainage dynamics of thin liquid films confined between a solid particle, an immiscible liquid droplet, and/or gas bubble. Equipped with a bimorph force sensor

如何提取黑体部分？

ps:目前可以把单词抽出来，并作词性分析，例如：[('A', 'DT'),('novel', 'NN'),('device', 'NN'), ('was', 'VBZ'),...],...