This attribute exists on the Python module, but we failed to convert Python type: 'list' to a TorchScript type

An error occurs when executing the code below.

import torch
import torch.nn as nn

class AAA(nn.Module):
    def __init__(self):
        super(AAA, self).__init__()

    def forward(self, x):
        return x


class BBB(nn.Module):
    def __init__(self, other: AAA=None):
        super(BBB, self).__init__()

        print(type([other]))
        self.other = [other]

    def forward(self, x):
        src = self.other[0]           # !!!Error!!!
        return x


if __name__ == '__main__':
    from utils.functions import init_console
    init_console()

    net_a = AAA()
    net_b = BBB(other=net_a)

    script_a = torch.jit.script(net_a)
    script_b = torch.jit.script(net_b)

    print('done')

Module ‘BBB’ has no attribute ‘other’ (This attribute exists on the Python module, but we failed to convert Python type: ‘list’ to a TorchScript type. Could not infer type of list element: Cannot infer concrete type of torch.nn.Module. Its type was inferred; try adding a type annotation for the attribute.):
File “C:/xxx/test.py”, line 20
def forward(self, x):
src = self.other[0]
~~~~~~~~~~ <— HERE
return x

Is there a way to make it work?