title: 'class_name' has no attribute 'attribute_name'
body: <p>look at this code plz :there is rules,In every instance the_oldets must refresh, Live is a abstract class</p>
  
  <pre><code>class Live(object):
      _the_oldest = 0
  
      def __init__(self,age,name):
          self.age=age
          self.name=name
  
      @classmethod
      def the_oldest(cls):
          if Live._the_oldest &lt; cls.age:
              Live._the_oldest=cls.age
  
      @staticmethod
      def Print(): 
          print(Live._the_oldest)
  
  
  class Dog(Live):
  
      def __init__(self,name,age):
          super().__init__(age,name)
          super().the_oldest()
  
  
  
  class Cat(Live):
      def __init__(self,name,age):
          super().__init__(age,name)
          super().the_oldest()
  </code></pre>
  
  <p>there is error :</p>
  
  <pre><code>&gt;&gt;&gt; db=Dog('doberman',12)
  AttributeError: type object 'Dog' has no attribute 'age'
  </code></pre>
  
  <p>I have changed code but nothing changed:</p>
  
  <pre><code>class Live(object):
      _the_oldest = 0
  
      def __init__(self):
          the_oldets(self)
  
      @classmethod
      def the_oldets(cls):
          if Live._the_oldest &lt; cls.age:
              Live._the_oldest=cls.age
  
      @staticmethod
      def Print(): 
          print(Live._the_oldest)
  
  
  
  class Dog(Live):
      def __init__(self,name,age):
          self.age=age
          self.name=name
  
  
  
  class Cat(Live):
      def __init__(self,name,age):
          self.age=age
          self.name=name
  </code></pre>
  
  <p>result:</p>
  
  <pre><code>&gt;&gt;&gt; db=Dog('doberman',12)
  &gt;&gt;&gt; db.the_oldets()
  AttributeError: type object 'Dog' has no attribute 'age'
  </code></pre>
  
  <p>why it happend !?  and how fix that ?</p>