diff --git a/.github/workflows/type_completeness.yml b/.github/workflows/type_completeness.yml
index 7ab7f6dc8..effa1dff0 100644
--- a/.github/workflows/type_completeness.yml
+++ b/.github/workflows/type_completeness.yml
@@ -50,6 +50,14 @@ jobs:
               json.load(open("pr.json", "rb"))["typeCompleteness"]["completenessScore"]
             )
             base_text = f"This PR changes type completeness from {round(base, 3)} to {round(pr, 3)}."
+            
+            if base == 0:
+                text = f"Something is broken in the workflow. Reported type completeness is 0. 💥"
+                set_summary(text)
+                print(Path("pr.readable").read_text(encoding="utf-8"))
+                error(text)
+                exit(1)
+            
             if pr < (base - 0.001):
                 text = f"{base_text} ❌"
                 set_summary(text)
diff --git a/telegram/ext/_jobqueue.py b/telegram/ext/_jobqueue.py
index 07bd678d3..14b3326fa 100644
--- a/telegram/ext/_jobqueue.py
+++ b/telegram/ext/_jobqueue.py
@@ -105,7 +105,7 @@ class JobQueue(Generic[CCT]):
 
         self._application: Optional[weakref.ReferenceType[Application]] = None
         self._executor = AsyncIOExecutor()
-        self.scheduler: AsyncIOScheduler = AsyncIOScheduler(**self.scheduler_configuration)
+        self.scheduler: "AsyncIOScheduler" = AsyncIOScheduler(**self.scheduler_configuration)
 
     def __repr__(self) -> str:
         """Give a string representation of the JobQueue in the form ``JobQueue[application=...]``.