title: Collection object is not callable error with PyMongo
body: <p>Following along the PyMongo <a href="http://api.mongodb.org/python/current/tutorial.html" rel="noreferrer">tutorial</a> and am getting an error when calling the <code>insert_one</code> method on a collection.</p>
  
  <pre><code>In [1]: import pymongo
  
  In [2]: from pymongo import MongoClient
  
  In [3]: client = MongoClient()
  
  In [4]: db = client.new_db
  
  In [5]: db
  Out[5]: Database(MongoClient('localhost', 27017), u'new_db')
  
  In [6]: posts = db.posts
  
  In [7]: posts.insert_one({'a':1})
  ---------------------------------------------------------------------------
  TypeError                                 Traceback (most recent call last)
  &lt;ipython-input-7-2271c01f9a85&gt; in &lt;module&gt;()
  ----&gt; 1 posts.insert_one({'a':1})
  
  C:\Anaconda\lib\site-packages\pymongo-2.8-py2.7-win32.egg\pymongo\collection.py in __call__(self, *a
  rgs, **kwargs)
     1771                         "call the '%s' method on a 'Collection' object it is "
     1772                         "failing because no such method exists." %
  -&gt; 1773                         self.__name.split(".")[-1])
  
  TypeError: 'Collection' object is not callable. If you meant to call the 'insert_one' method on a 'Collection' object it is failing because no such method exists.
  </code></pre>
  
  <p>There are a few posts online that discuss this error but all seem to be when the user calls a deprecated name.</p>
  
  <p>Any guidance on what I am doing wrong here?</p>