TypeError: issubclass() arg 1 must be a class

[Wang Jiaming]

transformer_pytorch/main.py

Line 20 in 76597a4

 DATASET = Multi30k() 

If someone runs the above code and gets the following error:

File "/home/user_name/anaconda3/envs/transformer_pytorch/lib/python3.9/typing.py", line 852, in __subclasscheck__
    return issubclass(cls, self.__origin__)
TypeError: issubclass() arg 1 must be a class

Then ensuring that the typing_extension is version 4.5.0 may fix this bug:

pip install typing_extensions==4.5.0