title: Adding values from loop to a tuple results in nested tuples instead of a flat tuple or list
body: <p>I'm trying to perform the following:</p>
  <pre><code>tup1 = ()
  for i in range(1, 10, 2):
      tup1 = (tup1, i)
  print tup1
  </code></pre>
  <p>I expect the output to be the sequence 1 to 10.
  However, I end up with the following:</p>
  <pre><code>((((((), 0), 2), 4), 6), 8)
  </code></pre>
  <p>What would be a correct way to meet the requirement?</p>