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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 _get_or_create_uaa(self, uaa):
 """ Returns a valid UAA instance for performing administrative functions on services. """

        if isinstance(uaa, predix.admin.uaa.UserAccountAuthentication):
            return uaa

        logging.debug("Initializing a new UAA")
        return predix.admin.uaa.UserAccountAuthentication()