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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _update_classmethod(self, oldcm, newcm):
 """Update a classmethod update."""

        # While we can't modify the classmethod object itself (it has no
        # mutable attributes), we *can* extract the underlying function
        # (by calling __get__(), which returns a method object) and update
        # it in-place.  We don't have the class available to pass to
        # __get__() but any object except None will do.
        self._update(None, None, oldcm.__get__(0), newcm.__get__(0))