rnnFusedPointwise no longer available in >=PyTorch 1.0

I had a codebase that runs fine in PyTorch 0.4 but whenever I try to run it using PyTorch 1.0+, it complains about the following import.

from torch.nn._functions.thnn import rnnFusedPointwise as fusedBackend

I use fusedBackend in the following code snippet.

if input.is_cuda:
    igates = F.linear(input, w_ih)
    hgates = F.linear(hx, w_hh)
    state = fusedBackend.LSTMFused.apply
    return state(igates, hgates, cx, b_ih, b_hh)

Is there any way I can fix the import error for PyTorch 1.0+?