title: Python: Remove Duplicate Items from Nested list
body: <pre><code>mylist = [[1,2],[4,5],[3,4],[4,3],[2,1],[1,2]]
  </code></pre>
  
  <p>I want to remove duplicate items, duplicated items can be reversed. The result should be :</p>
  
  <pre><code>mylist = [[1,2],[4,5],[3,4]]
  </code></pre>
  
  <p>How do I achieve this in Python?</p>