title: Python deque extendleft with a tuple?
body: <p>I have a <code>deque</code> with max length of 10.  Is is possible to <code>.extendleft</code> and add a tuple.  For example:</p>
  
  <pre><code>from collections import deque
  
  x = deque(maxlen = 10)
  z = [(1,4),(1,3),(2,5),(7,1),(6,4),(8,2),(9,1),(9,5),(7,3),(8,3)] 
  for y in z:
      x.append(y)
  print x
  x.extendleft((6,7))
  print x
  </code></pre>
  
  <p>Returns:</p>
  
  <pre><code>deque([(1, 4), (1, 3), (2, 5), (7, 1), (6, 4), (8, 2), (9, 1), (9, 5), (7, 3), (8, 3)], maxlen=10)
  deque([7, 6, (1, 4), (1, 3), (2, 5), (7, 1), (6, 4), (8, 2), (9, 1), (9, 5)], maxlen=10)
  </code></pre>
  
  <p>I tried:
      pair = (6,7)
      x.extendleft(pair)
  with the same results.</p>