Two COM Questions: QueryInterface, and Callback Inheritance

[Christopher Paulicka]

Hello,

I am using PythonWin, and the win32com extension.  Using genpy, I have made
class wrappers for the appropriated type library.

QUESTION ONE:
How to QueryInterface for a new dispatch interface?

For example:

>>>    import win32com.client
>>>    d = Dispatch("MyCoolThing.App")
>>>    s = d.GetOtherThing()

# Unfortunately, s is of class IMyInterface, and I want it to
# be for class IMyInterface2.
# The class exists in the genpy.
# How do I do the following type of thing?

>>>    s2 = s.QueryInterface("IMyInterface2")

# The above does not work.  Heh.  Neither does...

>>>    s2 = s.QueryInterface(IMyInterface2.CLSID)

# Is there a trivial way to do it?

QUESTION TWO:
How to subclass a class based on Dispatch?  Can it work at all?

For example:
>>>    import win32com.client
>>>    d = Dispatch("MyCoolThing.App")
>>>    s = d.GetOtherThing()

# s has a method, called SetCallback(), that takes a
#  Dispatch interface to IThingCallback.  There is a class in my
# genpy module called IThingCallback.
#  How can I do the following?  (Is it possible somehow?)

>>>    class MyCallback(IThingCallback):
                def Go(self, data):
                    print data
>>>    c = MyCallback()
>>>    s.SetCallback(c)


Thanks for all your help,

Christopher Paulicka