<s> from django . db import models <EOL> class ConcreteModel ( models . Model ) : <EOL> pass <EOL> class ProxyModel ( ConcreteModel ) : <EOL> class Meta : <EOL> proxy = True <EOL> class ConcreteModelSubclass ( ProxyModel ) : <EOL> pass <EOL> class ConcreteModelSubclassProxy ( ConcreteModelSubclass ) : <EOL> class Meta : <EOL> proxy = True </s>
