title: Python's re.split() not removing all matched characters
body: <p>This is driving me absolutely nuts. I am positive that the entire date range at the start of the string is being matched by the regex. Yet, when I do re.split, an <code>8</code> hangs behind. What's going on here and how can I split on that date range (in some cases it might be at the start and in the middle of the string, hence the split)?</p>
  
  <pre><code>import re
  a = "09/05/2018-12/18/2018 Lecture Wednesday 01:30PM - 02:45PM, Room to be Announced"
  b = r"([0-9]|\/|-){21}"
  print re.split(b, a)
  </code></pre>
  
  <p>Result</p>
  
  <pre><code>['', '8', ' Lecture Wednesday 01:30PM - 02:45PM, Room to be Announced']
  </code></pre>