Improve distutils and lib2to3 (#5763)

Add missing elements to distutils.util:

* run_2to3()
* copydir_run_2to3()
* Mixin2to3

Use PEP 604 and PEP 585.

Add lib2to3.refactor.

stdlib/lib2to3/refactor.pyi

@@ -0,0 +1,70 @@
+from collections.abc import Container, Generator, Iterable, Mapping
+from logging import Logger
+from typing import Any, ClassVar, NoReturn
+
+from .pgen2.grammar import Grammar
+
+_Driver = Any  # really lib2to3.driver.Driver
+_BottomMatcher = Any  # really lib2to3.btm_matcher.BottomMatcher
+
+def get_all_fix_names(fixer_pkg: str, remove_prefix: bool = ...) -> list[str]: ...
+def get_fixers_from_package(pkg_name: str) -> list[str]: ...
+
+class FixerError(Exception): ...
+
+class RefactoringTool:
+    CLASS_PREFIX: ClassVar[str]
+    FILE_PREFIX: ClassVar[str]
+    fixers: Iterable[str]
+    explicit: Container[str]
+    options: dict[str, Any]
+    grammar: Grammar
+    write_unchanged_files: bool
+    errors: list[Any]
+    logger: Logger
+    fixer_log: list[Any]
+    wrote: bool
+    driver: _Driver
+    pre_order: Any
+    post_order: Any
+    files: list[Any]
+    BM: _BottomMatcher
+    bmi_pre_order: list[Any]
+    bmi_post_order: list[Any]
+    def __init__(
+        self, fixer_names: Iterable[str], options: Mapping[str, Any] | None = ..., explicit: Container[str] | None = ...
+    ) -> None: ...
+    def get_fixers(self) -> tuple[list[Any], list[Any]]: ...
+    def log_error(self, msg: str, *args: Any, **kwds: Any) -> NoReturn: ...
+    def log_message(self, msg: str, *args: Any) -> None: ...
+    def log_debug(self, msg: str, *args: Any) -> None: ...
+    def print_output(self, old_text: str, new_text: str, filename: str, equal): ...
+    def refactor(self, items: Iterable[str], write: bool = ..., doctests_only: bool = ...) -> None: ...
+    def refactor_dir(self, dir_name: str, write: bool = ..., doctests_only: bool = ...) -> None: ...
+    def _read_python_source(self, filename: str) -> tuple[str, str]: ...
+    def refactor_file(self, filename: str, write: bool = ..., doctests_only: bool = ...) -> None: ...
+    def refactor_string(self, data: str, name: str): ...
+    def refactor_stdin(self, doctests_only: bool = ...) -> None: ...
+    def refactor_tree(self, tree, name: str) -> bool: ...
+    def traverse_by(self, fixers, traversal) -> None: ...
+    def processed_file(
+        self, new_text: str, filename: str, old_text: str | None = ..., write: bool = ..., encoding: str | None = ...
+    ) -> None: ...
+    def write_file(self, new_text: str, filename: str, old_text: str, encoding: str | None = ...) -> None: ...
+    PS1: ClassVar[str]
+    PS2: ClassVar[str]
+    def refactor_docstring(self, input: str, filename: str) -> str: ...
+    def refactor_doctest(self, block: list[str], lineno: int, indent: int, filename: str) -> list[str]: ...
+    def summarize(self) -> None: ...
+    def parse_block(self, block: Iterable[str], lineno: int, indent: int): ...
+    def wrap_toks(
+        self, block: Iterable[str], lineno: int, indent: int
+    ) -> Generator[tuple[Any, Any, tuple[int, int], tuple[int, int], str], None, None]: ...
+    def gen_lines(self, block: Iterable[str], indent: int) -> Generator[str, None, None]: ...
+
+class MultiprocessingUnsupported(Exception): ...
+
+class MultiprocessRefactoringTool(RefactoringTool):
+    queue: Any | None
+    output_lock: Any | None
+    def refactor(self, items: Iterable[str], write: bool = ..., doctests_only: bool = ..., num_processes: int = ...) -> None: ...