title: Multi-valued data in DynamoDB using boto
body: <p>After scouring the documentation and various tutorials, I cannot figure out how to set or update an attribute on a dynamo Item that is a multi-valued data type (number or string set). I'm using boto (boto.dynamodb2, to be specific -- not boto.dynamodb).</p>
  
  <p>Trying something like this (where 'id' is the hash key):</p>
  
  <pre><code>Item(Table('test'), data={'id': '123', 'content': 'test', 'list': [1,2,3,4]}).save()
  </code></pre>
  
  <p>Results in this error:</p>
  
  <pre><code>TypeError: Unsupported type "&lt;type 'list'&gt;" for value "[1, 2, 3, 4]"
  </code></pre>
  
  <p>I feel like this must be possible in boto.dynamodb2, but it's odd that I can't find any examples of people doing this. (Everyone is just setting number or string attributes, not number set or string set attributes.) </p>
  
  <p>Any insight on this topic and how I might get this to work with boto would be very much appreciated! I'm guessing I'm overlooking something simple. Thanks!</p>