Function error

crates/vm/src/stdlib/os.rs:2044–2050

(
            vm: &VirtualMachine,
            error: std::io::Error,
            path: OsPath,
        )

        #[cold]
        fn error(
            vm: &VirtualMachine,
            error: std::io::Error,
            path: OsPath,
        ) -> crate::builtins::PyBaseExceptionRef {
            OSErrorBuilder::with_filename(&error, path, vm)
        }

        let path = OsPath::try_from_object(vm, path)?;
        // TODO: just call libc::truncate() on POSIX