title: Finding unique list in list of list of tuples
body: <p>I have a list of lists of tuples:</p>
  <pre><code>x = [[(0,0),(0,1)],[(1,2),(2,3)],[(0,0),(0,1)],[(1,2),(2,3)]]
  </code></pre>
  <p>I want all the unique lists present in the list x</p>
  <p>My output should be:</p>
  <pre><code>x=[[(0,0),(0,1)],[(1,2),(2,3)]]
  </code></pre>
  <p>I tried using x=list(set(x)) but it gives error: 'list is not hashable', I also tried using numpy.unique but it does not give desired output. How can I implement this?</p>