title: Need help determining whether a user has answered "yes" or "no" using Python
body: <p>I am writing a mini-chatbot and I can't seem to figure out a way to determine whether a user has answered "yes" or "no". For example, if the user has typed "okay", I'd like to know that they have essentially answered "yes". Or, if they've written "nope", I'd like to know that they've essentially answered "no". </p>
  
  <p>Using nltk's wordnet hasn't been much of a help. Here is what I tried: </p>
  
  <pre><code>import nltk
  from nltk.corpus import wordnet as wn
  
  for syn in wn.synsets('yes'):
      print(syn.name(), syn.lemma_names())
  </code></pre>
  
  <p>I was hoping to get back something like <code>yes.n.01 ['yes', 'okay', 'sure', 'yup', 'yeah']</code>, but instead all I get is <code>yes.n.01 ['yes']</code>. I'm looking for a solution in Python, though it doesn't necessarily need to be through the nltk package.</p>