title: Determine seconds between two dates in Python
body: <p>I'm calling the Office 365 Calendar API and receiving the start date of the event back in the following format:</p>
  
  <p>2016-05-20T08:00:00Z</p>
  
  <p>I want to check when an event is near e.g. 5 minutes time, and use something along the lines of the following solution:
  [<a href="https://stackoverflow.com/questions/17259432/python-do-something-when-event-is-near][1]">Python - Do (something) when event is near</a></p>
  
  <p>What's the best way of determining the number of seconds between my event in the date/time format above and the current time now (in UTC taking into account daylight savings)?</p>