diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 21d770a2e5..198054e917 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -15,7 +15,7 @@ repos:
         pass_filenames: false
       - id: mypy
         name: mypy
-        entry: mypy tinygrad/ --check-untyped-defs --explicit-package-bases --warn-unreachable # --warn-return-any
+        entry: mypy tinygrad/ extra/helpers.py --check-untyped-defs --explicit-package-bases --warn-unreachable # --warn-return-any
         language: system
         always_run: true
         pass_filenames: false
diff --git a/extra/helpers.py b/extra/helpers.py
index 8c0f1bc902..0084963ef9 100644
--- a/extra/helpers.py
+++ b/extra/helpers.py
@@ -30,7 +30,7 @@ def proc(itermaker, q):
 def cross_process(itermaker, maxsize=8):
   # TODO: use cloudpickle for itermaker
   import multiprocessing
-  q = multiprocessing.Queue(maxsize)
+  q: multiprocessing.Queue = multiprocessing.Queue(maxsize)
   p = multiprocessing.Process(target=proc, args=(itermaker, q))
   p.daemon = True
   p.start()