title: How can you query begins_with for primary keys in DynamoDB?
body: <p>What's the best way to filter results with the begins_with method for boto3.dynamodb.condition.Key?</p>
  <pre><code>import boto3
  from boto3.dynamodb.conditions import Key
  
  dynamodb = boto3.resource('dynamodb')
  table = dynamodb.Table('MyTable')
  response = table.query(KeyConditionExpression=Key('myPrimaryKey').begins_with('americas'))
  </code></pre>
  <p>The results, although conditions supports begins_with, is the query is not supported. Can you not use begins_with on primary or sort keys?</p>