title: How do I specify input and output data types in python comments?
body: <p>I have seen several standards for writing comments about the kind of data a function expects and returns in Python. Is there a consensus on which one is best-practice? </p>
  
  <p>Is the new functionality in <a href="http://www.python.org/dev/peps/pep-3107/" rel="noreferrer">http://www.python.org/dev/peps/pep-3107/</a> something I should start using for this?</p>