docs/asyncio: Document new ensure_future() and deprecated async()
diff --git a/Doc/library/asyncio-stream.rst b/Doc/library/asyncio-stream.rst
index 41b24ac..e9638e3 100644
--- a/Doc/library/asyncio-stream.rst
+++ b/Doc/library/asyncio-stream.rst
@@ -364,7 +364,7 @@
 
     url = sys.argv[1]
     loop = asyncio.get_event_loop()
-    task = asyncio.async(print_http_headers(url))
+    task = asyncio.ensure_future(print_http_headers(url))
     loop.run_until_complete(task)
     loop.close()