Issue #18874: PyCode_New() now ensures that the filename is a ready Unicode
string. This change does nothing is most cases, but it is useful on Windows in
some cases.
Issue #18874: _PyObject_Malloc/Realloc/Free() now falls back on
_PyMem_RawMalloc/Realloc/Free, instead of _PyMem_Malloc/Realloc/Free.  So it
becomes possible to use the fast pymalloc allocator for the PYMEM_DOMAIN_MEM
domain (PyMem_Malloc/Realloc/Free functions).
Close #16742: Fix misuse of memory allocations in PyOS_Readline()

The GIL must be held to call PyMem_Malloc(), whereas PyOS_Readline() releases
the GIL to read input.

The result of the C callback PyOS_ReadlineFunctionPointer must now be a string
allocated by PyMem_RawMalloc() or PyMem_RawRealloc() (or NULL if an error
occurred), instead of a string allocated by PyMem_Malloc() or PyMem_Realloc().

Fixing this issue was required to setup a hook on PyMem_Malloc(), for example
using the tracemalloc module.

PyOS_Readline() copies the result of PyOS_ReadlineFunctionPointer() into a new
buffer allocated by PyMem_Malloc(). So the public API of PyOS_Readline() does
not change.
18764: remove the problematic 'print' alias for the PDB 'p' command.

So that it no longer shadows the print function.

Patch by Connor Osborn, doc and test changes by R. David Murray.
upgrade unicode db to 6.3.0 (closes #19221)
#18764: p(rint) -> p in pdb docs.

Missed changing the doc for the command itself, patch for that also by Connor
Osborn.
remove url from docstring (closes #19220)
merge 3.3 (#19220)
merge heads
make sure the docstring is never out of date wrt unicode data version
merge 3.3
replace hardcoded version
merge 3.3
Rename contextlib.ignored() to contextlib.ignore().