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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 from_thread(cls,thread):
 """Convert a vanilla thread object into an instance of this class. This method "upgrades" a vanilla thread object to an instance of this extended class. You might need to call this if you obtain a reference to a thread by some means other than (a) creating it, or (b) from the methods of the threading2 module. """

        new_classes = []
        for new_cls in cls.__mro__:
            if new_cls not in thread.__class__.__mro__:
                new_classes.append(new_cls)
        if isinstance(thread,cls):
            pass
        elif issubclass(cls,thread.__class__):
            thread.__class__ = cls
        else:
            class UpgradedThread(thread.__class__,cls):
                pass
            thread.__class__ = UpgradedThread
        for new_cls in new_classes:
            if hasattr(new_cls,"_upgrade_thread"):
                new_cls._upgrade_thread(thread)
        return thread