Max/Min value of Dictionary of List
<p>I have a dictionary mapping an id_ to a list of data values like so: <code>dic = {id_ : [v1, v2, v3, v4]}</code>.
I'm trying to iterate through every value in the dictionary and retrieve the max/min of a certain index of the list mappings.</p>

<p>What I want to do is something like this:</p>

<pre><code>maximum = max([data[0], ??) for id_, data in self.dic.items()])
</code></pre>

<p>...but obviously this will not work. Is it possible to do this in one line as above?</p>
