title: python 3 Call child attribute from parent method
body: <p>Can't call child attribute in parent method, here's the test:</p>
  
  <pre><code>#!/usr/bin/env python3
  
  class A():
      def getPath(self):
          return self.__path
  
  class B(A):
  
      def __init__( self, name, path):
          self.__name = name
          self.__path = path
  
  instance = B('test', '/home/test/Projects')
  
  print(instance.getPath())
  </code></pre>
  
  <p>Running python test file <code>$ ./test.py</code> returns</p>
  
  <pre><code>./test.py 
  Traceback (most recent call last):
    File "./test.py", line 17, in &lt;module&gt;
      print(instance.getPath())
    File "./test.py", line 6, in getPath
      return self.__path
  AttributeError: 'B' object has no attribute '_A__path'
  </code></pre>