title: AWS boto3 -- Difference between `batch_writer` and `batch_write_item`
body: <p>I'm currently applying boto3 with dynamodb, and I noticed that there are two types of batch write</p>
  
  <p><code>batch_writer</code> is used in tutorial, and it seems like you can just iterate through different JSON objects to do insert (this is just one example, of course)</p>
  
  <p><code>batch_write_items</code> seems to me is a dynamo-specific function. However, I'm not 100% sure about this, and I'm not sure what's the difference between these two functions (performance, methodology, what not)</p>
  
  <p>Do they do the same thing? If they are, why having 2 different functions? If they're not, what's the difference? How's the performance comparison?</p>