Python Dictionary append value error
<p>I'm trying to append a value (list) to a dictionary unsuccessfully. setting the value by 'equal' works, but appending doesn't.</p>

<pre><code>DurationDict = dict()
DurationDict[str(curYear)] = duration  // This works
DurationDict[str(curYear)].append(duration) //This does't work.
</code></pre>

<p>any ideas?</p>