How to get the output txt file for the instance segmentation results of cityscapes datasets

[YunlongHuu]

I am a beginner of detectron2. And I am dealing with some tasks of cityscapes datasets.
I use a command of "python train.py --config-file xxx --num-gpus --evel-only xx MODEL.WEIGHTS xxx DATASETS.TEST '("cityscapes_fine_instance_seg_test")'" While I cannot get the output file.
Can anybody provide some help for me about the true command to use or some file to modify?