`is_from` failing on pytorch model

[Matthieu Le Goff]

is_from method is only looling at the first element of the dependency model.

model = torch.hub.load("chenyaofo/pytorch-cifar-models", "cifar10_resnet20", pretrained=True)
is_from(model, "torch")
# returns False instead of True
# > class_parents = ['pytorch_cifar_models', 'torch', 'object']

It should look at all elements from class_parents and check if torch is in it. Maybe a unit test on models defined in the test of the TorchFeatureExtractor could be useful and reproduce the bug above.

[Paul Novello]

I patched the function in the very last PR.