Hi Mohit,
Looks like I made a mistake in the instructions. This should work:
qconfig = torch.quantization.get_default_qconfig('fbgemm')
print(torch.backends.quantized.supported_engines) # Prints the quantized backends that are supported
# Set the backend to what is needed. This needs to be consistent with the option you used to select the qconfig
torch.backends.quantized.engine='fbgemm'