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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 list_types(self):
 """ Returns a list of all available notification types. """

        uri = "/notification_types"
        resp, resp_body = self.api.method_get(uri)
        return [CloudMonitorNotificationType(self, info)
                for info in resp_body["values"]]