TypeError: resolve_type_from_object()

[za13]

I tried

source venv/bin/activate

python train.py --evaluate --snapshot checkpoints/best_cityscapes_checkpoint.pth

and got the error below:

Traceback (most recent call last):
  File "train.py", line 19, in <module>
    from utils.misc import AverageMeter, prep_experiment, evaluate_eval, fast_hist
  File "/home/me/Desktop/GSCNN/utils/misc.py", line 18, in <module>
    import torchvision.transforms as standard_transforms
  File "/home/me/Desktop/GSCNN/venv/lib/python3.5/site-packages/torchvision/__init__.py", line 3, in <module>
    from torchvision import models
  File "/home/me/Desktop/GSCNN/venv/lib/python3.5/site-packages/torchvision/models/__init__.py", line 12, in <module>
    from . import detection
  File "/home/me/Desktop/GSCNN/venv/lib/python3.5/site-packages/torchvision/models/detection/__init__.py", line 1, in <module>
    from .faster_rcnn import *
  File "/home/me/Desktop/GSCNN/venv/lib/python3.5/site-packages/torchvision/models/detection/faster_rcnn.py", line 14, in <module>
    from .roi_heads import RoIHeads
  File "/home/me/Desktop/GSCNN/venv/lib/python3.5/site-packages/torchvision/models/detection/roi_heads.py", line 210, in <module>
    @torch.jit.script
  File "/home/me/Desktop/GSCNN/venv/lib/python3.5/site-packages/torch/jit/__init__.py", line 1290, in script
    fn = torch._C._jit_script_compile(qualified_name, ast, _rcb, get_default_args(obj))
  File "/home/me/Desktop/GSCNN/venv/lib/python3.5/site-packages/torch/jit/_recursive.py", line 568, in try_compile_fn
    return torch.jit.script(fn, _rcb=rcb)
  File "/home/me/Desktop/GSCNN/venv/lib/python3.5/site-packages/torch/jit/__init__.py", line 1290, in script
    fn = torch._C._jit_script_compile(qualified_name, ast, _rcb, get_default_args(obj))
  File "/home/me/Desktop/GSCNN/venv/lib/python3.5/site-packages/torch/jit/__init__.py", line 2030, in _get_overloads
    compiled_fns.append(_compile_function_with_overload(overload_fn, qual_name, obj))
  File "/home/me/Desktop/GSCNN/venv/lib/python3.5/site-packages/torch/jit/__init__.py", line 2010, in _compile_function_with_overload
    overload_signature = torch.jit.annotations.get_signature(overload_fn, None, None, inspect.ismethod(overload_fn))
  File "/home/me/Desktop/GSCNN/venv/lib/python3.5/site-packages/torch/jit/annotations.py", line 79, in get_signature
    signature = parse_type_line(type_line, rcb, loc)
  File "/home/me/Desktop/GSCNN/venv/lib/python3.5/site-packages/torch/jit/annotations.py", line 165, in parse_type_line
    arg_types = [ann_to_type(ann, loc) for ann in arg_ann]
  File "/home/me/Desktop/GSCNN/venv/lib/python3.5/site-packages/torch/jit/annotations.py", line 165, in <listcomp>
    arg_types = [ann_to_type(ann, loc) for ann in arg_ann]
  File "/home/me/Desktop/GSCNN/venv/lib/python3.5/site-packages/torch/jit/annotations.py", line 303, in ann_to_type
    the_type = try_ann_to_type(ann, loc)
  File "/home/me/Desktop/GSCNN/venv/lib/python3.5/site-packages/torch/jit/annotations.py", line 296, in try_ann_to_type
    the_type = torch._C._resolve_type_from_object(ann, loc, fake_rcb)
TypeError: _resolve_type_from_object(): incompatible function arguments. The following argument types are supported:
    1. (arg0: object, arg1: torch._C._jit_tree_views.SourceRange, arg2: Callable[[str], function]) -> torch._C.Type

Invoked with: typing.Union[int, NoneType], None, <function try_ann_to_type.<locals>.fake_rcb at 0x7fb1b275fe18>