Issue #21493: Added test for ntpath.expanduser().  Original patch by
Claudiu Popa.
Issue #21402: tkinter.ttk now works when default root window is not set.
Restore performance of some dumb database methods (regression introduced by #19385).
Issue #21376: document asyncio.TimeoutError
Issue #21454: Fix asyncio.BaseEventLoop.connect_read_pipe doc

The function sets the the pipe to non-blocking mode.
Issue #21477: Add htests for GrepDialog, UndoDelegator, and configDialog.
Put instructions in a fixed size scrollable Text. Patch by Saimadhav Heblikar.