bpo-33649: Add low-level APIs index. (GH-9364)

diff --git a/Doc/library/asyncio-eventloop.rst b/Doc/library/asyncio-eventloop.rst
index 3e1571f..909d3ea3 100644
--- a/Doc/library/asyncio-eventloop.rst
+++ b/Doc/library/asyncio-eventloop.rst
@@ -980,7 +980,7 @@
 Executing code in thread or process pools
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-.. method:: loop.run_in_executor(executor, func, \*args)
+.. coroutinemethod:: loop.run_in_executor(executor, func, \*args)
 
    Arrange for a *func* to be called in the specified executor.
 
@@ -1418,7 +1418,7 @@
 like :func:`asyncio.run`.
 
 
-.. _asyncio-hello-world-callback:
+.. _asyncio_example_lowlevel_helloworld:
 
 Hello World with call_soon()
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -1451,7 +1451,7 @@
    example created with a coroutine and the :func:`run` function.
 
 
-.. _asyncio-date-callback:
+.. _asyncio_example_call_later:
 
 Display the current date with call_later()
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -1488,7 +1488,7 @@
    created with a coroutine and the :func:`run` function.
 
 
-.. _asyncio-watch-read-event:
+.. _asyncio_example_watch_fd:
 
 Watch a file descriptor for read events
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -1531,15 +1531,17 @@
 
 .. seealso::
 
-   * A similar :ref:`example <asyncio-register-socket>`
+   * A similar :ref:`example <asyncio_example_create_connection>`
      using transports, protocols, and the
      :meth:`loop.create_connection` method.
 
-   * Another similar :ref:`example <asyncio-register-socket-streams>`
+   * Another similar :ref:`example <asyncio_example_create_connection-streams>`
      using the high-level :func:`asyncio.open_connection` function
      and streams.
 
 
+.. _asyncio_example_unix_signals:
+
 Set signal handlers for SIGINT and SIGTERM
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^