title: Group list of dictionaries by value
body: <p>I have a list of dictionaries. How can i group that list by valaues.</p>
  
  <pre><code>list = [{a:1},{b:2},{c:1},{d:3},{e:2}]
  </code></pre>
  
  <p>Now my result should be like below</p>
  
  <pre><code>1:a,c
  2:b,e
  3:d
  </code></pre>
  
  <p>I tried using <code>groupby</code> from <code>itertools</code>. But i couldn't get the required result. I am using python 2.7.</p>
  
  <p>Could you help me achieve this?</p>