class Evaluator(object):
  def __init__(self, value):
    self._value = value
  def is_odd(self):
    return self._value % 2 == 1
  def is_positive(self):
    return self._value > 0

def main():
  e = Evaluator(4)
  if e.is_odd():
    print "It's odd!"
  else:
    print "It's even!"

main()