Remove stray semicolon
diff --git a/Lib/threading.py b/Lib/threading.py
index d907c89..5d68a9e 100644
--- a/Lib/threading.py
+++ b/Lib/threading.py
@@ -1143,7 +1143,7 @@
         if not self._initialized:
             raise RuntimeError("Thread.__init__() not called")
         if self._started.is_set():
-            raise RuntimeError("cannot set daemon status of active thread");
+            raise RuntimeError("cannot set daemon status of active thread")
         self._daemonic = daemonic
 
     def isDaemon(self):