redirect all calls to _get_action_name to action.get_name
remove all _log lines (an issue specific test)
_metavar_formatter return fnc now takes None, when the return should be
a string rather than tuple; less logic in _format_action_invocation

CompactHelpFormatter - shortten the help header ('-f/--foo FOO')

need more cleanup of logic re. get_name, metavar_formatter, and other
places that test for length of metavar
Move check_argument to action.check_nargs

cleanup use of _() in error messages

add the empty parts cleanup in _format_actions_usage
(should add the relevant tests (long wrap with suppress MXG)
argparse - add 9625 (check_value) for * defaults
action._check_values() - handle multiple values as well as one
called by alt version of _get_values
move the logic of positional * default handling to
_eval_start_default() function
2 versions - maximal passing value through get_value and check
minimal - no action (more like other list defaults)

test_argparse - add tests for
issue 9625, 18349, 16360, 17890 (from composite)