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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 available_metrics(self):
 """ List all available metrics that you can add to this machine :returns: A list of dicts, each of which is a metric that you can add to a monitored machine """

        req = self.request(self.mist_client.uri+"/clouds/"+self.cloud.id+"/machines/"+self.id+"/metrics")
        metrics = req.get().json()
        return metrics