title: Python: update dictionary key with tuple values
body: <p>I have a dictionary that has keys with two values each. I need to update the second value as pass duplicate keys. 
  Clearly what I'm trying isn't working out. </p>
  
  <hr>
  
  <pre><code>if value1 not in dict.keys():
      dict.update({key:(value1,value2)})
  else:
      dict.update({key:value1,+1)})
  </code></pre>
  
  <p>this just returned a diction with 1s for value 2 instead of incrementing by 1</p>