title: Boto3 DynamoDB update list attributes for an item
body: <p>I have a table like:</p>
  
  <pre><code>{
  "pKey": 10001,
  "items": [
      {
          "name": "A",
          "value": 100
      },
      {
          "name": "B",
          "value": 100
      }
  ]
  }
  </code></pre>
  
  <p>I would like to update all <code>value</code> attributes in <code>items</code> list to be 200, <code>items</code> list can have 1 to n objects.</p>
  
  <p>How can I do that using boto3 python dynamoDB low-level client APIs?</p>