Marked keystrokes with the :kbd: role.
Fixed the case of the "Ctrl-" prefixes.
diff --git a/Doc/library/asyncio-protocol.rst b/Doc/library/asyncio-protocol.rst
index 2e671e8..02a1b68 100644
--- a/Doc/library/asyncio-protocol.rst
+++ b/Doc/library/asyncio-protocol.rst
@@ -539,7 +539,7 @@
     coro = loop.create_server(EchoServerClientProtocol, '127.0.0.1', 8888)
     server = loop.run_until_complete(coro)
 
-    # Serve requests until CTRL+c is pressed
+    # Serve requests until Ctrl+C is pressed
     print('Serving on {}'.format(server.sockets[0].getsockname()))
     try:
         loop.run_forever()