bpo-18802: Add more details to ipaddress documentation (GH-6083)


Original patch by Jon Foster and Berker Peksag.
(cherry picked from commit 5609b78392d59c7362ef8aa5c4a4529325f01f27)

Co-authored-by: Cheryl Sabella <cheryl.sabella@gmail.com>
diff --git a/Lib/test/test_ipaddress.py b/Lib/test/test_ipaddress.py
index dbf68b3..a5aeb79 100644
--- a/Lib/test/test_ipaddress.py
+++ b/Lib/test/test_ipaddress.py
@@ -404,6 +404,9 @@
 class NetmaskTestMixin_v4(CommonTestMixin_v4):
     """Input validation on interfaces and networks is very similar"""
 
+    def test_no_mask(self):
+        self.assertEqual(str(self.factory('1.2.3.4')), '1.2.3.4/32')
+
     def test_split_netmask(self):
         addr = "1.2.3.4/32/24"
         with self.assertAddressError("Only one '/' permitted in %r" % addr):