Fix lint in test_nn.py (#18006)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/18006
ghimport-source-id: e267ece1ac03e0d17e01dddf4a77f52421859435
Stack:
* **#18006 Fix lint in test_nn.py**
Signed-off-by: Edward Z. Yang <ezyang@fb.com>
Reviewed By: eellison
Differential Revision: D14458108
fbshipit-source-id: 18ee6199447efed55a922cff5b3ad940a21c0536
