class Super:
  def __init__(self):
    self.data1 = 'spam'
  def ham(self): pass

class ListTree:
  def __str__(self):
    self.__visited = {}
    return '<Instance of {0}, adress {1}:n{2}{3}>'.format(
      self.__class__.__name__,
      id(self),
      self.__attrnames(self, 0),
      self.__listclass(self.__class__, 4))
  def __listclass(self, aClass, indent):
    dots = '.' * indent
    if aClass in self.__visited:
      return 'n{0}<Class {1}:, address {2}: (see above)>n'.format(
        dots,
        aClass,__name__,
        id(aClass))
    else:
      self.__visited[aClass] = True
      genabove = (self.__listclass(c, indent+4) for c in aClass.__bases__)
      return 'n{0}<Class {1}, address {2}:n{3}{4}{5}n'.format(
        dots,
        aClass.__name__,
        id(aClass),
        self.__attrnames(aClass, indent),
        ''.join(genabove),
        dots)
  def __attrnames(self, obj, indent):
    spaces = ' ' * (indent + 4)
    result = ''
    for attr in sorted(obj.__dict__):
      if attr.startswith('__') and attr.endswith('__'):
        result += spaces + '{0}=<>n'.format(attr)
      else:
        result += spaces + '{0}={1}n'.format(attr, getattr(obj, attr))
    return result


class Sub(Super, ListTree):
  pass


a = Sub()
print(a)