Why isn't __new__ in Python new-style classes a class method?

__new__ being static method allows a use-case when you create an instance of a subclass in it:

return super(<currentclass>, cls).__new__(subcls, *args, **kwargs)

If new is a class method then the above is written as:

return super(<currentclass>, cls).new(*args, **kwargs)

and there is no place to put subcls.

I don't really see when that would be a proper use of __new__, though. Maybe I'm not seeing it, but that just seems to me to be a completely pathological use of it (and it should be said, that if you still really want it, then you could access it with object.__new__.__func__). At the very least, I find it very hard to imagine that it would have been the reason for Guido to change __new__ from being a class method to a static method.

A more common case would be to call parent __new__ without using super(). You need a place to pass cls explicitly in this case:

class Base(object):    @classmethod    def new(cls):        print("Base.new(%r)" % (cls,))        return cls()class UseSuper(Base):    @classmethod    def new(cls):        print("UseSuper.new(%r)" % (cls,))        return super(UseSuper, cls).new() # passes cls as the first argclass NoSuper(Base):    @classmethod    def new(cls):        print("NoSuper.new(%r)" % (cls,))        return Base.new()  # passes Base as the first argclass UseFunc(Base):    @classmethod    def new(cls):        print("UseFunc.new(%r)" % (cls,))        return Base.new.im_func(cls)  # or `.__func__(cls)`. # passes cls as the first argprint(UseSuper.new())print('-'*60)print(NoSuper.new())print('-'*60)print(UseFunc.new())