title: strptime() does not convert string to datetime object in Python 3.6
body: <p>I am getting an exception when I run the following code which I can not explain:</p>
  
  <pre><code>import datetime
  datetime.datetime.strptime("2018-04-02", format = "%Y-%m-%d")
  
  TypeError: strptime() takes no keyword arguments
  </code></pre>