Issue #27830: Add _PyObject_FastCallKeywords(): avoid the creation of a
temporary dictionary for keyword arguments.
Other changes:
* Cleanup call_function() and fast_function() (ex: rename nk to nkwargs)
* Remove now useless do_call(), replaced with _PyObject_FastCallKeywords()
Issue #27213: Rework CALL_FUNCTION* opcodes to produce shorter and more
efficient bytecode:
* CALL_FUNCTION now only accepts position arguments
* CALL_FUNCTION_KW accepts position arguments and keyword arguments, but keys
of keyword arguments are packed into a constant tuple.
* CALL_FUNCTION_EX is the most generic, it expects a tuple and a dict for
positional and keyword arguments.
CALL_FUNCTION_VAR and CALL_FUNCTION_VAR_KW opcodes have been removed.
2 tests of test_traceback are currently broken: skip test, the issue #28050 was
created to track the issue.
Patch by Demur Rumed, design by Serhiy Storchaka, reviewed by Serhiy Storchaka
and Victor Stinner.
Issue #27830: Similar to _PyObject_FastCallDict(), but keyword arguments are
also passed in the same C array than positional arguments, rather than being
passed as a Python dict.
Issue #27809: PyEval_CallObjectWithKeywords() doesn't increment temporary the
reference counter of the args tuple (positional arguments). The caller already
holds a strong reference to it.
Issue #27128. When a Python function is called with no arguments, but all
parameters have a default value: use default values as arguments for the fast
path.
