Python, loop through list within a range
<p>I have a list with the values 0 to 30.</p>

<p>How can I loop through these values (within a range) with an added offset?</p>

<p>As that might not make any sense, I've made a little diagram:</p>

<p><img src="http://i.imgur.com/xBayFb0.png" alt="diagram"></p>
