Library
-------
+- Issue #20566: Change asyncio.as_completed() to use a Queue, to
+ avoid O(N**2) behavior.
+
+- Issue #20704: Implement new debug API in asyncio. Add new methods
+ BaseEventLoop.set_debug() and BaseEventLoop.get_debug().
+ Add support for setting 'asyncio.tasks._DEBUG' variable with
+ 'PYTHONASYNCIODEBUG' environment variable.
+
+- asyncio: Refactoring and fixes: BaseEventLoop.sock_connect() raises an
+ error if the address is not resolved; use __slots__ in Handle and
+ TimerHandle; as_completed() and wait() raise TypeError if the passed
+ list of Futures is a single Future; call_soon() and other 'call_*()'
+ functions raise TypeError if the passed callback is a coroutine
+ function; _ProactorBasePipeTransport uses _FlowControlMixin;
+ WriteTransport.set_write_buffer_size() calls _maybe_pause_protocol()
+ to consider pausing receiving if the watermark limits have changed;
+ fix _check_resolved_address() for IPv6 address; and other minor
+ improvements, along with multiple documentation updates.
+
- Issue #20684: Fix inspect.getfullargspec() to not to follow __wrapped__
chains. Make its behaviour consistent with bound methods first argument.
Patch by Nick Coghlan and Yury Selivanov.