title: Pymongo Updating Differently than Mongo Shell
body: <p>While using Pymongo for updates, I do not get a result (or an error) that I get if I drop the same query into a shell, where <code>db=blog</code></p>
  
  <p>In the shell, this works:</p>
  
  
  
  <pre class="lang-js prettyprint-override"><code>db.posts.update(
      {'permalink': 'TLxrBfyxTZjqOKqxgnUP'},
      {'$inc': {'comments.0.num_likes':1}});
  </code></pre>
  
  <p>While in Pymongo where <code>self.posts = blog.posts</code>, the following does not work</p>
  
  <pre class="lang-js prettyprint-override"><code>self.posts.update({'permalink': 'TLxrBfyxTZjqOKqxgnUP'},
        {'$inc': {'comments.0.num_likes':1}})
  </code></pre>
  
  <p>I have also tried <code>comments.[0].num_likes</code> on a flyer...</p>
  
  <p>There are no errors reported in the logs, and while this update returns 1 as the number of documents touched, which is correct, that data has not been altered.</p>
  
  <p>Other non-indexed updates do work in both.</p>
  
  <p>What am I missing here?</p>
  
  <p>Thank you!</p>