Fix the name resolution for exception (#640)
Fix the name resolution for exception (#640)

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Just fixed minor `name`  resolution
Pull Request resolved: https://github.com/facebookresearch/detectron2/pull/640

Differential Revision: D19297720

Pulled By: ppwwyyxx

fbshipit-source-id: a4a4c82efdcd13e60b5c34e31cfb164e6b83565a

facebookresearch/detectron2,facebookresearch/detectron2,facebookresearch/detectron2