class Critter(object):      '''A virtual pet'''      def __init__(self, name):          print 'A new critter has been born!'          self.__name = name        def get_name(self):          return self.__name        def set_name(self, new_name):          if new_name == '':              print 'A critter's name can't be the empty string.'          else:              self.__name = new_name              print 'Name change successful.'        name = property(get_name, set_name)        def talk(self):          print '\nHi, I'm', self.name    # main  crit = Critter('Poochie')  crit.talk()    print '\nMy critter's name is:',  print crit.name  print '\nAttempting to change my critter's name.'  crit.name = ''  print '\nAttempting to change my critter's name again.'  crit.name = 'Randolph'    crit.talk()