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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 protocols(self):
 """ Returns a list of available load balancing protocols. """

        if self._protocols is None:
            uri = "/loadbalancers/protocols"
            resp, body = self.method_get(uri)
            self._protocols = [proto["name"] for proto in body["protocols"]]
        return self._protocols