Best way to reduce dictionary of lists
<p>I am asking this question to get a starting point of the Pythonic way to reduce some of the list contents in the following dictionary using list comprehensions:</p>

<pre><code>{'cycle1': [1, 2407, 2393, 14],
 'cycle2': [2, 1657, 1652, 5], 
 'cycle3': [3, 2698, 2673, 25], 
 'cycle4': [4, 2116, 2102, 14], 
 'cycle5': [5, 2065, 2048, 17], 
 'cycle6': [6, 1633, 1615, 18]}
</code></pre>

<p>Each list's columns, though not marked, have these headers:</p>

<pre><code>section_num,account_total,billable_count,nonbillable_count
</code></pre>

<p>I want to sum each of the last three columns, account_total, billable_count, non-billable_count in a list comprehension. </p>

<p>I'm just not sure how to sum going through each list member in a comprehension. I need to ask for the values of each key, each value being a list. I'm just a little unsure about how to do that.</p>
