Fix windows python 3.8 loading path (#2747)

Summary:
Fix windows python 3.8 loading path

Pull Request resolved: #2747

Reviewed By: nateanl

Differential Revision: D40264326

Pulled By: nateanl

fbshipit-source-id: f4a24757de7b48c63a7481034eb11fc3ff174327

torchaudio/_extension.py

@@ -91,12 +91,16 @@ def _init_extension():
     # To find cuda related dlls we need to make sure the
     # conda environment/bin path is configured Please take a look:
     # https://stackoverflow.com/questions/59330863/cant-import-dll-module-in-python
+    # Please note: if some path can't be added using add_dll_directory we simply ignore this path
     if os.name == "nt" and sys.version_info >= (3, 8) and sys.version_info < (3, 9):
         env_path = os.environ["PATH"]
         path_arr = env_path.split(";")
         for path in path_arr:
             if os.path.exists(path):
-                os.add_dll_directory(path)
+                try:
+                    os.add_dll_directory(path)
+                except Exception:
+                    pass
 
     _load_lib("libtorchaudio")
     # This import is for initializing the methods registered via PyBind11