Do Python for loops work by reference?
<p>When using a <code>for</code> loop in Python to iterate over items in a list, will changing <code>item</code> (below) change the corresponding item in <code>items</code>?</p>

<pre><code>for item in items:
    item += 1
</code></pre>

<p>Will each item in items be incremented or remain the same as before the loop?</p>

<p>[Note: I would be interested in Python 2.7 and 3.x]</p>
