I wrote the following code snippet and it gave me the following error
torch version 1.4.0
torchvision version 0.5.0
I tried installing using both pip and conda. Both produces the same error
import torchvision

RuntimeError                              Traceback (most recent call last)
 in 
----> 1 import torchvision
~/anaconda3/lib/python3.7/site-packages/torchvision/init.py in 
1 import warnings
2
----> 3 from torchvision import models
4 from torchvision import datasets
5 from torchvision import ops
~/anaconda3/lib/python3.7/site-packages/torchvision/models/init.py in 
10 from .shufflenetv2 import *
11 from . import segmentation
—> 12 from . import detection
13 from . import video
14 from . import quantization
~/anaconda3/lib/python3.7/site-packages/torchvision/models/detection/init.py in 
----> 1 from .faster_rcnn import *
2 from .mask_rcnn import *
3 from .keypoint_rcnn import *
~/anaconda3/lib/python3.7/site-packages/torchvision/models/detection/faster_rcnn.py in 
11
12 from .generalized_rcnn import GeneralizedRCNN
—> 13 from .rpn import AnchorGenerator, RPNHead, RegionProposalNetwork
14 from .roi_heads import RoIHeads
15 from .transform import GeneralizedRCNNTransform
~/anaconda3/lib/python3.7/site-packages/torchvision/models/detection/rpn.py in 
9 from torchvision.ops import boxes as box_ops
10
—> 11 from . import _utils as det_utils
12 from .image_list import ImageList
13
~/anaconda3/lib/python3.7/site-packages/torchvision/models/detection/_utils.py in 
17
18 @torch.jit.script
—> 19 class BalancedPositiveNegativeSampler(object):
20     “”"
21     This class samples batches, ensuring that they contain a fixed proportion of positives
~/anaconda3/lib/python3.7/site-packages/torch/jit/init.py in script(obj, optimize, _frames_up, _rcb)
1217         use :func:@torch.jit.ignore <torch.jit.ignore>.
1218
-> 1219         Example (an exported and ignored method in a module)::
1220
1221             import torch
~/anaconda3/lib/python3.7/site-packages/torch/jit/init.py in _compile_and_register_class(obj, rcb, qualified_name)
1074
1075 def _try_get_overloaded_fn(mod, field):
-> 1076     return mod._overloads.get(field, None) if isinstance(mod, ScriptModule) else None
1077
1078
RuntimeError: class ‘torch.torchvision.models.detection._utils.BalancedPositiveNegativeSampler’ already defined. (register_type at /pytorch/torch/csrc/jit/script/compilation_unit.h:166)
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