def __getattribute__(self, item):
        """Allow class attribute names in EXTEND_BASE_CLASS_ATTRIBUTES that are
        defined on subclasses to automatically extend the equivalently named
        attribute on this base class

        (a bit of an ugly hack, but hey, it's only the admin)
        """
        value = super().__getattribute__(item)
        if item in EXTEND_BASE_CLASS_ATTRIBUTES and value is not None:
            base_value = getattr(ModelAdmin, item)
            base_value.update(value)
            return base_value
        return value
def __getattribute__ ( self , item ) : value = super ( ) . __getattribute__ ( item ) if item in EXTEND_BASE_CLASS_ATTRIBUTES and value is not None : base_value = getattr ( ModelAdmin , item ) base_value . update ( value ) return base_value return value
Allow class attribute names in EXTEND_BASE_CLASS_ATTRIBUTES that are
        defined on subclasses to automatically extend the equivalently named
        attribute on this base class

        (a bit of an ugly hack, but hey, it's only the admin)