No, but there are some ways to convert your image.

You could add the conversation to your Dataset and just convert the image after loading it:

from skimage import io, color
class MyData(Dataset):
    ...
    def __getitem__(self, index):
        rgb = io.imread(self.images[index])
        lab = color.rgb2lab(rgb)
        x = torch.from_numpy(lab)
        ...


You could try to implement the conversion in PyTorch, if you really need to apply this function on a Tensor.
Adobe has an older cookbook 199 for the conversion.

I hope it helps!