When i trian the model,I got this issue.

Traceback (most recent call last):
File "tools/run_net.py", line 42, in
main()
File "tools/run_net.py", line 23, in main
launch_job(cfg=cfg, init_method=args.init_method, func=train)
File "/home/leo/my_project/SlowFast/slowfast/utils/misc.py", line 296, in launch_job
func(cfg=cfg)
File "/home/leo/my_project/SlowFast/tools/train_net.py", line 393, in train
train_loader = loader.construct_loader(cfg, "train")
File "/home/leo/my_project/SlowFast/slowfast/datasets/loader.py", line 83, in construct_loader
dataset = build_dataset(dataset_name, cfg, split)
File "/home/leo/my_project/SlowFast/slowfast/datasets/build.py", line 31, in build_dataset
return DATASET_REGISTRY.get(name)(cfg, split)
File "/home/leo/my_project/SlowFast/slowfast/datasets/kinetics.py", line 74, in __init__
self._construct_loader()
File "/home/leo/my_project/SlowFast/slowfast/datasets/kinetics.py", line 94, in _construct_loader
== 2
AssertionErro