def fill_unfilled(self, exc_info: tuple[type[E], E, TracebackType]) -> None:
        """Fill an unfilled ExceptionInfo created with ``for_later()``."""
        assert self._excinfo is None, "ExceptionInfo was already filled"
        self._excinfo = exc_info
Fill an unfilled ExceptionInfo created with ``for_later()``.
src/_pytest/_code/code.py