title: Perform set operation difference on a list of tuples
body: <p><strong>I am trying to get the difference between 2 containers but the containers are in a weird structure so I dont know whats the best way to perform a difference on it.</strong> One containers type and structure I cannot alter but the others I can(variable delims).</p>
  
  <pre><code>delims = ['on','with','to','and','in','the','from','or']
  words = collections.Counter(s.split()).most_common()
  # words results in [("the",2), ("a",9), ("diplomacy", 1)]
  
  #I want to perform a 'difference' operation on words to remove all the delims words
  descriptive_words = set(words) - set(delims)
  
  # because of the unqiue structure of words(list of tuples) its hard to perform a difference
  # on it. What would be the best way to perform a difference? Maybe...
  
  delims = [('on',0),('with',0),('to',0),('and',0),('in',0),('the',0),('from',0),('or',0)]
  words = collections.Counter(s.split()).most_common()
  descriptive_words = set(words) - set(delims)
  
  # Or maybe
  words = collections.Counter(s.split()).most_common()
  n_words = []
  for w in words:
     n_words.append(w[0])
  delims = ['on','with','to','and','in','the','from','or']
  descriptive_words = set(n_words) - set(delims)
  </code></pre>