bpo-35934: Add socket.create_server() utility function (GH-11784)

Lib/test/test_asyncio/functional.py

@@ -60,21 +60,13 @@ class FunctionalTestCaseMixin:
             else:
                 addr = ('127.0.0.1', 0)
 
-        sock = socket.socket(family, socket.SOCK_STREAM)
-
+        sock = socket.create_server(addr, family=family, backlog=backlog)
         if timeout is None:
             raise RuntimeError('timeout is required')
         if timeout <= 0:
             raise RuntimeError('only blocking sockets are supported')
         sock.settimeout(timeout)
 
-        try:
-            sock.bind(addr)
-            sock.listen(backlog)
-        except OSError as ex:
-            sock.close()
-            raise ex
-
         return TestThreadedServer(
             self, sock, server_prog, timeout, max_clients)