fix secure tab

venv/lib/python3.9/site-packages/gevent/tests/test__loop_callback.py

@@ -0,0 +1,18 @@
+from gevent import get_hub
+from gevent import testing as greentest
+
+class Test(greentest.TestCase):
+    def test(self):
+        count = [0]
+
+        def incr():
+            count[0] += 1
+
+        loop = get_hub().loop
+        loop.run_callback(incr)
+        loop.run()
+        self.assertEqual(count, [1])
+
+
+if __name__ == '__main__':
+    greentest.main()