diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index b83d245..b8666c0 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -119,7 +119,7 @@ jobs:
       run: black --check .
 
     - name: Check with mypy
-      if: ${{ !startsWith(matrix.python-version, 'pypy') && matrix.python-version >= '3.7' }}
+      if: ${{ !startsWith(matrix.python-version, 'pypy') }}
       run: mypy
 
     - name: Lint with flake8
diff --git a/requirements_test.txt b/requirements_test.txt
index 58e630b..d123263 100644
--- a/requirements_test.txt
+++ b/requirements_test.txt
@@ -1,7 +1,7 @@
 pytest
 coverage==5.5
 black==23.3.0
-typing-extensions==4.5.0
+typing-extensions==4.7.1
 
 # Only for CPython (exclude pypy).
 celery-types==0.14.0; implementation_name != 'pypy'
diff --git a/tests/test_pubsub.py b/tests/test_pubsub.py
index 07a8707..febdf89 100644
--- a/tests/test_pubsub.py
+++ b/tests/test_pubsub.py
@@ -19,7 +19,6 @@
 from celery_pubsub import publish, unsubscribe, publish_now
 
 P = ParamSpec("P")
-R = typing.TypeVar("R")
 
 
 def test_subscription(job_c: Task[P, str], celery_worker: WorkController) -> None: