bpo-37120: Add SSLContext.num_tickets (GH-13719)

Signed-off-by: Christian Heimes <christian@python.org>
diff --git a/Lib/test/test_ssl.py b/Lib/test/test_ssl.py
index 455a12e..7ba8156 100644
--- a/Lib/test/test_ssl.py
+++ b/Lib/test/test_ssl.py
@@ -1634,6 +1634,24 @@
         obj = ctx.wrap_bio(ssl.MemoryBIO(), ssl.MemoryBIO())
         self.assertIsInstance(obj, MySSLObject)
 
+    @unittest.skipUnless(IS_OPENSSL_1_1_1, "Test requires OpenSSL 1.1.1")
+    def test_num_tickest(self):
+        ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_SERVER)
+        self.assertEqual(ctx.num_tickets, 2)
+        ctx.num_tickets = 1
+        self.assertEqual(ctx.num_tickets, 1)
+        ctx.num_tickets = 0
+        self.assertEqual(ctx.num_tickets, 0)
+        with self.assertRaises(ValueError):
+            ctx.num_tickets = -1
+        with self.assertRaises(TypeError):
+            ctx.num_tickets = None
+
+        ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
+        self.assertEqual(ctx.num_tickets, 2)
+        with self.assertRaises(ValueError):
+            ctx.num_tickets = 1
+
 
 class SSLErrorTests(unittest.TestCase):