title: count the number of occurrences of a certain value in a dictionary in python?
body: <p>If I have got something like this:</p>
  
  <pre><code>D = {'a': 97, 'c': 0 , 'b':0,'e': 94, 'r': 97 , 'g':0}
  </code></pre>
  
  <p>If I want for example to count the number of occurrences for the "0" as a value without having to iterate the whole list, is that even possible and how?</p>