title: Initialize dictionary, loop through list, add words and increment counter in dictionary
body: <p>I've added an example to hopefully make this clearer. I'm trying to do the following: add words from sentence that aren't in words dict to a list, then take those words and add them to a dictionary 'new_words_dict'. Only add words once, no duplicates, and increment a counter to track how many times the word appears. For example, 'happy' would appear in the dictionary once with a counter of 2.</p>
  
  <p>I'm able to create the list and add words to the dictionary, but I'm not incrementing the value in the dictionary correctly.</p>
  
  <pre><code>words = {'abandon':-2,'abandoned':-2,'abandons':-2,'abducted':-2,'abduction':-2,
  'abductions':-2,'abhor': -3}
  sentence = {'abandon', 'abandoned', 'abhorrent', 'hello', 'smart', 'hello', 'die',
  'happy', 'sad', 'up', 'down', 'happy', 'smart','cool', 'clean', 'mean'}         
  
  new_words_list = []                  #Empty list
  new_words_dict = {}                  #Empty dict 
  
  for word in sentence:
  if word not in words:    
          new_words_list.append(word)  
  print new_words_list        
  
  for word in new_words_list:
      if word not in new_words_dict:
          new_words_dict[word] = {}
          new_words_dict[word] =1
  else:
      if word in new_words_dict:
          new_words_dict[word] +=1              
  print new_words_dict
  </code></pre>
  
  <p>This prints the new_words_dict, but the value counters don't increment correctly.</p>