class A:
      def __init__(self):
        self.test = "hmm"

      def A_M(self, change):
        self.test = change

      def getTest(self):
        return self.test

      class B:
          def __init__(self, obj):
            self.obj = obj

          def C(self):
            print self.obj.getTest()
            self.obj.A_M("hello")
            print self.obj.getTest()

    a = A()
    a.B(a).C()

    #a.A_M has been changed to "hello"!
    print a.getTest()