title: python's shortcut for len(list(filter(lambda x: criteria, iterable)))
body: <p>Imagine you need to count number of <code>iterable</code> elements that satisfy some <code>criteria</code> - is there is a more good looking way to do this?
  It's python3 of course. But 2 is fine too.
  I can't find anything suitable in <code>collections</code> or <code>itertools</code> python modules or in built-ins.</p>