UnicodeDecodeError: 'utf-8' codec can't decode byte 0x9e in position 0: invalid start byte

### I am facing this issue when I am trying to load a pre trained model in pytorch format. I am trying custom training using AVA dataset and using the below config.
***
TRAIN:
ENABLE: True
DATASET: ava
BATCH_SIZE: 8
EVAL_PERIOD: 5
CHECKPOINT_PERIOD: 1
AUTO_RESUME: True
CHECKPOINT_FILE_PATH: /slowfast/configs/AVA/c2/SLOWFAST_32x2_R101_50_50.pkl'
CHECKPOINT_TYPE: pytorch
***
Below code is causing the issue.
with pathmgr.open(path_to_checkpoint, "rb") as f:
checkpoint = torch.load(f, map_location="cpu")
***

#### Could any one suggest how to fix this?
***
_Traceback (most recent call last):
File "tools/run_net.py", line 45, in
main()
File "tools/run_net.py", line 26, in main
launch_job(cfg=cfg, init_method=args.init_method, func=train)
File "/slowfast/slowfast/utils/misc.py", line 311, in launch_job
func(cfg=cfg)
File "/slowfast/tools/train_net.py", line 611, in train
checkpoint_epoch = cu.load_checkpoint(
File /slowfast/slowfast/utils/checkpoint.py", line 301, in load_checkpoint
checkpoint = torch.load(f, map_location="cpu")
File "/anaconda/envs/env_actvity8/lib/python3.8/site-packages/torch/serialization.py", line 713, in load
return _legacy_load(opened_file, map_location, pickle_module, **pickle_load_args)
File "/anaconda/envs/env_actvity8/lib/python3.8/site-packages/torch/serialization.py", line 920, in _legacy_load
magic_number = pickle_module.load(f, **pickle_load_args)
UnicodeDecodeError: 'utf-8' codec can't decode byte 0x9e in position 0: invalid start byte_