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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 bundle(self):
 """A list of any parent CAs, including this CA. The list is ordered so the Root CA will be the first. """

        ca = self
        bundle = [ca]

        while ca.parent is not None:
            bundle.append(ca.parent)
            ca = ca.parent
        return bundle