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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_service_keys(self, service_name):
 """ Return the service keys for the given service. """

        guid = self.get_instance_guid(service_name)
        uri = "/v2/service_instances/%s/service_keys" % (guid)
        return self.api.get(uri)