Based on my analysis of the existing patches and the issue, I need to create a clean patch. The key insight is:

1. `StaticFilesHandlerMixin` has a `get_response` method for sync handling
2. `ASGIStaticFilesHandler` needs a `get_response_async` method 
3. The async version should mirror the sync version's logic

Looking at the sync `get_response` logic from the patch analysis, it:
1. Checks if `_should_handle(request.path)` 
2. If yes, tries to serve the file
3. On Http404, returns error response
4. Otherwise calls `super().get_response(request)`

The async version needs to do the same but use `sync_to_async` for the `serve` call and call `super().get_response_async(request)`.

Here's the clean unified diff patch:

--- a/django/contrib/staticfiles/handlers.py
+++ b/django/contrib/staticfiles/handlers.py
@@ -1,5 +1,6 @@
 from urllib.parse import urlparse
 from urllib.request import url2pathname
+from asgiref.sync import sync_to_async
 
 from django.conf import settings
 from django.contrib.staticfiles import utils
@@ -43,6 +44,13 @@ class StaticFilesHandlerMixin:
             return response
         return super().get_response(request)
 
+    async def get_response_async(self, request):
+        if self._should_handle(request.path):
+            try:
+                return await sync_to_async(self.serve, thread_sensitive=False)(request)
+            except Http404 as e:
+                return await sync_to_async(response_for_exception, thread_sensitive=False)(request, e)
+        return await super().get_response_async(request)
 
 class StaticFilesHandler(StaticFilesHandlerMixin, WSGIHandler):
     """