apex needed

[QingZhong1996]

I have already used the following command for inference
"python scripts/inference.py configs/opensora-v1-2/inference/sample.py
--num-frames 4s --resolution 720p
--layernorm-kernel False --flash-attn False
--prompt "a beautiful waterfall"",
but I am still encountering an error requiring the installation of apex.

"Traceback (most recent call last):
File "/./projects/Open-Sora/scripts/inference.py", line 304, in
main()
File "//projects/Open-Sora/scripts/inference.py", line 289, in main
save_path = save_sample(
File "//myconda/envs/opensora/lib/python3.9/site-packages/opensora/datasets/utils.py", line 178, in save_sample
write_video(save_path, x, fps=fps, video_codec="h264")
File "//myconda/envs/opensora/lib/python3.9/site-packages/torchvision/io/video.py", line 132, in write_video
frame.pict_type = "NONE"
File "av/video/frame.pyx", line 193, in av.video.frame.VideoFrame.pict_type.set
TypeError: an integer is required
/myconda/envs/opensora/lib/python3.9/site-packages/colossalai/pipeline/schedule/_utils.py:19: UserWarning: torch.utils._pytree.register_pytree
node is deprecated. Please use torch.utils._pytree.register_pytree_node instead.
_register_pytree_node(OrderedDict, _odict_flatten, _odict_unflatten)
/myconda/envs/opensora/lib/python3.9/site-packages/torch/utils/_pytree.py:254: UserWarning: <class 'collections.OrderedDict'> is already registered as pytree node. Overwriting the previous registration.
warnings.warn(
/myconda/envs/opensora/lib/python3.9/site-packages/colossalai/shardformer/layer/normalization.py:45: UserWarning: Please install apex from source (https://github.com/NVIDIA/apex) to use the fused layernorm kernel
warnings.warn("Please install apex from source (https://github.com/NVIDIA/apex) to use the fused layernorm kernel")"

[rfww]

Hello, how to solve the issue of "TypeError: an integer is required"?