Create dynamic stack of context managers

context_manager_stack.py

from contextlib import AbstractContextManager
import sys
from types import TracebackType


class ContextManagerStack(AbstractContextManager):
    def __init__(self, *contextManagers: AbstractContextManager) -> None:
        self._contextManagers = contextManagers
        self._enteredContexts: list[AbstractContextManager] = []

    def __enter__(self) -> tuple[object, ...]:
        res: list[object] = []
        for cm in self._contextManagers:
            try:
                r = cm.__enter__()
            except Exception:
                self.__exit__(*sys.exc_info())
            else:
                res.append(r)
            self._enteredContexts.append(cm)
        return tuple(res)
    
    def __exit__(self, excType: type[BaseException] | None, excValue: BaseException | None, traceback: TracebackType | None) -> None:
        excs: list[Exception] = []
        if excValue is not None:
            excs.append(excValue)
        while self._enteredContexts:
            cm = self._enteredContexts.pop()
            try:
                cm.__exit__(excType, excValue, traceback)
            except Exception as e:
                excs.append(e)
        if excs:
            raise ExceptionGroup("Multiple exceptions in ContextManagerStack", excs)