Fix version test in detr

Summary: TorchVision recently upgrade their version to 0.10.0 which causes issues in the version check in detr.

Reviewed By: wat3rBro

Differential Revision: D27575085

fbshipit-source-id: 75f459fe7a711161e908609fcf2f2d28a01a6c74

projects_oss/detr/detr/util/misc.py

@@ -20,7 +20,8 @@ from torch import Tensor
 
 # needed due to empty tensor bug in pytorch and torchvision 0.5
 import torchvision
-if float(torchvision.__version__[:3]) < 0.7:
+from distutils.version import LooseVersion
+if LooseVersion(torchvision.__version__) < LooseVersion("0.7.0"):
     from torchvision.ops import _new_empty_tensor
     from torchvision.ops.misc import _output_size