Make PyTorch importable on python-3.7.0 (#78500)
By stringifying "typing.OrderedDict", as [`typing.OrderedDict`](https://docs.python.org/3.10/library/typing.html#typing.OrderedDict) were introduced by Python-3.7.2+
See similar fix in https://github.com/pytorch/pytorch/commit/21a82fb5194d2a079c752215a8f87e36ddc2f6b6
Partially addresses https://github.com/pytorch/pytorch/issues/78499
Pull Request resolved: https://github.com/pytorch/pytorch/pull/78500
Approved by: https://github.com/atalman
