human
Solve the following python programming problem given the following code:
def register(self, name, class_ = None) : 
    '
        Accepts a ``name`` and ``class_``, a class object that must extend
        ``base``. The class is added to the registry.::

            named_registry.register("My Class", MyClass)

        If no ``class_`` is provided. A class decorator (callable) is returned
        that is bound to the given ``name`` and accepts one arguement,
        ``_class``. This allows for the following use of the register method::

            @named_registry.register("My Class")
            class MyClass:
                pass

        The exception ``appregister.base.AlreadyRegistered`` is raised if the
        class has already been registered, as defined by the ``is_registered``
        method.

        The exception ``appregister.base.InvalidOperation`` is raised if the
        class is not a valid addition to this register, as defined by the
        ``is_valid`` method.
        ' 
    if self.is_registered (name) : 
        msg = ("Object '%s' has already been registered" % class_.__name__) 
        raise AlreadyRegistered (msg) 
if (not class_) : 
        def inner(class_) : 
            return self.register (name, class_) 
return inner 
if (not self.is_valid (class_)) : 
        msg = ("Object '%s' is not a subclass of '%s'" % (class_.__name__, inner.base.__name__)) 
        raise InvalidOperation (msg) 
self._registry [name] = class_ 
    return class_ 

    
    

    Fix the buggy line: msg = ("Object '%s' is not a subclass of '%s'" % (class_.__name__, inner.base.__name__))
assistant
#Here is Python program to fix the buggy line: msg = ("Object '%s' is not a subclass of '%s'" % (class_.

msg = ("Object '%s' is not a subclass of '%s'" % (class_.__name__, self.base.__name__))