title: Update self variable within __init__ everytime it is called in python
body: <p>I want a self variable within <strong>init</strong> to update every time it is called  e.g. every time I execute <code>Data(10).plot</code>, self.plot should reinitialise by parsing the self.n to the Plot class.</p>
  
  <pre><code>class Data(object):
      def __init__(self, n):
          self.n = n
          self.plot = Plot(self.n)
  
      def minus(self, x):
          self.n -= x
          return self.n
  
  
  class Plot(object):
      def __init__(self, n):
          self.n = n
  
      def double(self):
          return self.n * 2
  </code></pre>
  
  <p>Another example: When I execute the following code, I want the answer variable to equal 16. Instead it equals 20. How do I implement this behaviour within the above classes?</p>
  
  <pre><code>data = Data(10)
  data.minus(2)
  answer = vcf.plot.double())
  </code></pre>