raise AttributeError(name)

遇到问题如下：

Traceback (most recent call last):
  File "keras_retinanet/bin/", line 426, in <module>
    main()
  File "keras_retinanet/bin/", line 362, in main
    train_generator, validation_generator = create_generators(args)
  File "keras_retinanet/bin/", line 190, in create_generators
    batch_size=args.batch_size
  File "keras_retinanet/bin/../../keras_retinanet/preprocessing/pascal_voc.py", line 92, in __init__
    super(PascalVocGenerator, self).__init__(**kwargs)
  File "keras_retinanet/bin/../../keras_retinanet/preprocessing/", line 60, in __init__
    self.group_images()
  File "keras_retinanet/bin/../../keras_retinanet/preprocessing/", line 166, in group_images
    (key=lambda x: self.image_aspect_ratio(x))
  File "keras_retinanet/bin/../../keras_retinanet/preprocessing/", line 166, in <lambda>
    (key=lambda x: self.image_aspect_ratio(x))
  File "keras_retinanet/bin/../../keras_retinanet/preprocessing/pascal_voc.py", line 109, in image_aspect_ratio
    return float() / float()
  File "/usr/lib/python2.7/dist-packages/PIL/", line 608, in __getattr__
    raise AttributeError(name)
AttributeError: width

解决方法:

pip install --upgrade Pillow