def instance(instance_group_name, index_or_id, options = { deployment_name: Deployments::DEFAULT_DEPLOYMENT_NAME })
      find_instance(instances(options), instance_group_name, index_or_id)
    end
def instance(instance_group_name, index_or_id, options = { deployment_name: Deployments::DEFAULT_DEPLOYMENT_NAME })
      find_instance(instances(options), instance_group_name, index_or_id)
    end
vm always returns a vm