title: Parsing a time instant in python
body: <p>I am relatively new to python. 
  I have a timestamp of the format - 2016-12-04T21:16:31.265Z. It is of a type string. I want to know how can I parse the above timestamp in python. </p>
  
  <p>I was looking through the datetime library, but seems like it accepts only floats. How do I get the time stamp parsed? I was trying to hunt for something like an equivalent of Instant (in java) for python?</p>