Issue #20334. Thanks to Antony Lee for bug report & initial patch.

Both compileall.compile_dir() and the CLI for compileall now allow for
specifying how many workers to use (or 0 to use all CPUs).

Thanks to Claudiu Popa for the patch.

The PyMem_Malloc(size) function has a well defined behaviour: if size is 0, a
pointer different than NULL is returned. PyMem_Malloc() allocations are
tracked by tracemalloc, attemptckalloc() allocations are not tracked.

It was failed when run with non-empty current directory.

character instead of truncate it.  Based on patch by Victor Stinner.

character instead of truncate it.  Based on patch by Victor Stinner.

 subdirectories using the "**" pattern.

empty string or tuple argument.

On some platforms Tcl memory allocator returns NULL when allocating zero-sized
block of memory.

empty string or tuple argument.

On some platforms Tcl memory allocator returns NULL when allocating zero-sized
block of memory.

ckalloc() causes the Tcl interpreter to panic, attemptckalloc() returns NULL
if the memory allocation fails.

ckalloc() causes the Tcl interpreter to panic, attemptckalloc() returns NULL
if the memory allocation fails.

failure.

self-contained, this change facilitates maintenance and the Python version
can be easily imported for experimentation.

Original patch by Tarek Ziadé.

  a package's __init__.py.  TestLoader.loadTestsFromModule() still accepts
  use_load_tests, but it is deprecated and ignored.  A new keyword-only
  attribute `pattern` is added and documented.  Patch given by Robert Collins,
  tweaked by Barry Warsaw.

Patch from Thomas Kluyver.

First letter no longer is stripped from the "status" key in
the result of Treeview.heading().

First letter no longer is stripped from the "status" key in
the result of Treeview.heading().

a pipe in _ipconfig_getnode().

Optimized bytes and bytes_le properties of UUID and UUID constructor with
bytes_le argument.

Fixed a bug in handling an error occured during reading from a pipe in
_ipconfig_getnode().

response is received.  Patch by Martin Panter.