title: How to remove duplicates form string array
body: <p>I have an string array that contains json strings . Is it possible to identify and remove all the records which contains the same uid ?</p>
  
  <pre><code>{"object":"user","entry":[{"uid":"823602904340066","id":"823602904340066","time":1429276535,"changed_fields":["feed"]}]}
  
  {"object":"user","entry":[{"uid":"10203227586595390","id":"10203227586595390","time":1429278537,"changed_fields":["feed"]}]}
  
  {"object":"user","entry":[{"uid":"10203227586595390","id":"10203227586595390","time":1429278531,"changed_fields":["feed"]}]}
  </code></pre>