title: close() never close connections in pymongo?
body: <p>I use MongoDB and I connect to it through pymongo. Here's my code:</p>
  
  <pre><code>&gt;&gt;&gt; import pymongo
  &gt;&gt;&gt; con=pymongo.Connection('localhost',27017)
  &gt;&gt;&gt; con.database_names()
  ['local', 'bookdb']
  &gt;&gt;&gt; con.close()
  &gt;&gt;&gt; con.database_names()
  ['local', 'bookdb']
  </code></pre>
  
  <p>I use <code>con.close()</code> to disconnect to the MongoDB, but after that, I can still use  <code>con.database_names()</code>  to see the list of the databases. Why? it never disconnect to the MongoDB server. Why the <code>close()</code> not work? </p>