Queue is apparently not subscriptable in py3.8

Author: cosmicexplorer

src/pip/_internal/network/download.py

@@ -159,7 +159,7 @@ def __call__(self, link: Link, location: str) -> Tuple[str, str]:
 
 
 def _copy_chunks(
-    output_queue: Queue[Union[Tuple[Link, Path, Optional[str]], BaseException]],
+    output_queue: "Queue[Union[Tuple[Link, Path, Optional[str]], BaseException]]",
     event: Event,
     semaphore: Semaphore,
     session: PipSession,
@@ -222,7 +222,7 @@ def __call__(
         # Set up state to track thread progress, including inner exceptions.
         total_downloads: int = len(links)
         completed_downloads: int = 0
-        q: Queue[Union[Tuple[Link, Path, Optional[str]], BaseException]] = Queue()
+        q: "Queue[Union[Tuple[Link, Path, Optional[str]], BaseException]]" = Queue()
         event = Event()
         # Limit downloads to 10 at a time so we can reuse our connection pool.
         semaphore = Semaphore(value=10)