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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_clouds(self):
 """ Request a list of all added clouds. Populates self._clouds dict with mist.client.model.Cloud instances """

        req = self.request(self.uri + '/clouds')
        clouds = req.get().json()
        if clouds:
            for cloud in clouds:
                self._clouds[cloud['id']] = Cloud(cloud, self)
        else:
            self._clouds = {}