code: def count(fn, coll):
      
      return len([x for x in coll if fn(x) is True])
docs: Return the count of True values returned by the predicate function applied to the
      collection
  
      :param fn: a predicate function
      :param coll: a collection
      :returns: an integer
  
      >>> count(lambda x: x % 2 == 0, [11, 22, 31, 24, 15])
      2