title: NLTK. Find if a sentence is in a questioning form
body: <p>I am trying to detect if a sentence is a question or a statement. Apart from looking for a question mark at the end of the sentence, is there another way to detect this? I am processing Twitter posts and people are not necessarily following good practises like question marks on Twitter.</p>
  
  <p>Reference to other libraries is also ok with me if <a href="http://www.nltk.org/" rel="noreferrer">nltk</a> does now work.</p>