pep-0492: Update PEP 3152 section

pep-0492.txt

@@ -748,7 +748,23 @@ Differences from this proposal:
    and having ``__call__`` and no ``__cocall__`` for coroutine-
    generators.
 
-6. There are no equivalents of ``async for`` and ``async with`` in PEP
+6. Requiring parentheses grammatically also introduces a whole lot
+   of new problems.
+
+   Code like the following::
+
+       await fut
+       await function_returning_future()
+       await asyncio.gather(coro1(arg1, arg2), coro2(arg1, arg2))
+
+    would look like::
+
+       cocall fut()  # or cocall costart(fut)
+       cocall (function_returning_future())()
+       cocall asyncio.gather(costart(coro1, arg1, arg2),
+                             costart(coro2, arg1, arg2))
+
+7. There are no equivalents of ``async for`` and ``async with`` in PEP
    3152.