title: Slicing behavior of python range()[:]
body: <p>I came across an interesting bit of code in a QC review and was surprised by its behavior. I am curious if it is documented anywhere.</p>
  
  <pre><code>for i in range(0, my_array.max(), 3)[:]:
      # other code here
  </code></pre>
  
  <p>I was curious about the need for the <code>[:]</code> after <code>range</code>, so I tested it:</p>
  
  <pre><code>&gt;&gt;&gt; range(0, 10, 3)
  range(0, 10, 3)
  &gt;&gt;&gt; range(0, 10, 3)[:]
  range(0, 12, 3)
  </code></pre>
  
  <p>The actual sequence defined by these ranges is identical, but I do not see this slicing behavior documented anywhere in the Python <a href="https://docs.python.org/3/library/stdtypes.html#ranges" rel="noreferrer">range</a> documentation, so I was curious what is actually going on here.</p>