misc: update threading monkeypatch for Python 3 (#37986)

wcs/qommon/__init__.py

@@ -132,26 +132,47 @@ class _MainThread(TenantAwareThread):
         self._Thread__delete()
 
 
-class _DummyThread(TenantAwareThread):
+if six.PY2:
+    class _DummyThread(TenantAwareThread):
 
-    def __init__(self):
-        super(_DummyThread, self).__init__(name=threading._newname("Dummy-%d"))
+        def __init__(self):
+            super(_DummyThread, self).__init__(name=threading._newname("Dummy-%d"))
 
-        # Thread.__block consumes an OS-level locking primitive, which
-        # can never be used by a _DummyThread.  Since a _DummyThread
-        # instance is immortal, that's bad, so release this resource.
-        del self._Thread__block
+            # Thread.__block consumes an OS-level locking primitive, which
+            # can never be used by a _DummyThread.  Since a _DummyThread
+            # instance is immortal, that's bad, so release this resource.
+            del self._Thread__block
 
-        self._Thread__started.set()
-        self._set_ident()
-        with threading._active_limbo_lock:
-            threading._active[threading._get_ident()] = self
+            self._Thread__started.set()
+            self._set_ident()
+            with threading._active_limbo_lock:
+                threading._active[threading._get_ident()] = self
 
-    def _set_daemon(self):
-        return True
+        def _set_daemon(self):
+            return True
 
-    def join(self, timeout=None):
-        assert False, "cannot join a dummy thread"
+        def join(self, timeout=None):
+            assert False, "cannot join a dummy thread"
+else:
+    class _DummyThread(TenantAwareThread):
+
+        def __init__(self):
+            super(_DummyThread, self).__init__(name=threading._newname("Dummy-%d"), daemon=True)
+
+            self._started.set()
+            self._set_ident()
+            with threading._active_limbo_lock:
+                threading._active[self._ident] = self
+
+        def _stop(self):
+            pass
+
+        def is_alive(self):
+            assert not self._is_stopped and self._started.is_set()
+            return True
+
+        def join(self, timeout=None):
+            assert False, "cannot join a dummy thread"
 
 
 class AppConfig(django.apps.AppConfig):