fast-stable-diffusion: Xformers Error

Discussed in https://github.com/TheLastBen/fast-stable-diffusion/discussions/1936

<div type='discussions-op-text'>

^{Originally posted by HaikenEdge April 3, 2023} I’m getting this error when I try to run “Start Stable-Diffusion” cell of the notebook:

/usr/local/lib/python3.9/dist-packages/torchvision/transforms/functional_tensor.py:5: UserWarning: The torchvision.transforms.functional_tensor module is deprecated in 0.15 and will be **removed in 0.17**. Please don't rely on it. You probably just need to use APIs in torchvision.transforms.functional or in torchvision.transforms.v2.functional.
  warnings.warn(
WARNING[XFORMERS]: xFormers can't load C++/CUDA extensions. xFormers was built for:
    PyTorch 1.13.1+cu117 with CUDA 1107 (you have 2.0.0+cu118)
    Python  3.9.16 (you have 3.9.16)
  Please reinstall xformers (see https://github.com/facebookresearch/xformers#installing-xformers)
  Memory-efficient attention, SwiGLU, sparse and more won't be available.
  Set XFORMERS_MORE_DETAILS=1 for more details

Not sure what’s causing it or how to fix it.</div>