Chapter 2: cnn_learner on bear images gives PIL transparency warning

[juliangilbey]

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In the cell which reads:

learn = cnn_learner(dls, resnet18, metrics=error_rate)
learn.fine_tune(4)

I'm getting the warning:

/home/jdg/fast.ai.course/fastai-venv/lib/python3.9/site-packages/PIL/Image.py:951: UserWarning: Palette images with Transparency expressed in bytes should be converted to RGBA images
  warnings.warn(

I'm not sure whether this is a fastbook or fastai issue.