title: While removing the duplicates i got this unhasable type: 'list' error !!!TypeError: unhashable type: 'list'
body: <pre><code>data_keys=list(set(data_keys))
  print data_keys
  </code></pre>
  
  <p>I tried to remove the duplicate keys in this list and i found this error. </p>
  
  <p>i am looking for simple solution for this. </p>
  
  <p>Error Message:</p>
  
  <pre><code>data_keys=list(set(data_keys))
  TypeError: unhashable type: 'list'
  </code></pre>