Extra base class in hierarchy

[Victor Porton]

Consider

class FinalTreeNode(object):
    def childs(self):
        return []

class UsualTreeNode(FinalTreeNode)
    def childs(self):
        return ...

In this structure UsualTreeNode derives from FinalTreeNode.

Is it better to introduce an extra base class?

class BaseTreeNode(object):
    def childs(self):
        return []

# The same functionality as BaseTreeNode, but logically distinct
class FinalTreeNode(BaseTreeNode):
    pass

# Not derived from FinalTreeNode, because it is not logically final
class UsualTreeNode(BaseTreeNode)
    def childs(self):
        return ...

-- 
Victor Porton - http://portonvictor.org