code: def child(self, index):
          
  
          if not self.__children:
              return
  
          if index >= 0 and index < len(self.__children):
              return self.__children[index]
docs: Returns the child associated with given index.
  
          Usage::
  
              >>> node_b = AbstractCompositeNode("MyNodeB")
              >>> node_c = AbstractCompositeNode("MyNodeC")
              >>> node_a = AbstractCompositeNode("MyNodeA", children=[node_b, node_c])
              >>> node_a.child(0)
              <AbstractCompositeNode object at 0x10107b6f0>
              >>> node_a.child(0).name
              u'MyNodeB'
  
          :param index: Child index.
          :type index: int
          :return: Child node.
          :rtype: AbstractNode or AbstractCompositeNode or Object