new_contents: class Facade(object):
      def __init__(self):
          self.a = ClassA()
          self.b = ClassB()
          self.c = ClassC()
      def execute(self):
          self.a.printA()
          self.b.printB()
          self.c.printC()
  
  
  class ClassA(object):
      def __init__(self):
          self.b = ClassB()
          self.c = ClassC()
  
      def printA(self):
          self.b.printB()
          self.c.printC()
  
  class ClassB(object):
      def printB(self):
          print "B"
  
  class ClassC(object):
      def printC(self):
          print "C"
  
  if __name__ == '__main__':
      facade = Facade()
      facade.execute()
  
subject: Add Facade.py