title: In MongoDB's pymongo, how do I do a count()?
body: <pre><code>for post in db.datasets.find({&quot;test_set&quot;:&quot;abc&quot;}).sort(&quot;abc&quot;,pymongo.DESCENDING).skip((page-1)*num).limit(num):
  </code></pre>
  <p>How do I get the <code>count()</code>?</p>