def METHOD_NAME(var_name: str) -> Callable:  # type: ignore
    """Check if the source selection exists"""
    # pylint: disable=no-self-argument
    def check_accepts(func_in: Callable) -> Callable:
        def new_f(self, *args, **kwds) -> Callable:  # type: ignore
            if kwds.get(var_name, None) is None:
                return func_in(self, *args, **kwds)
            for search_source in kwds[var_name].split(","):
                if Path(search_source) not in [
                    s.filename for s in self.review_manager.settings.sources
                ]:
                    raise colrev_exceptions.ParameterError(
                        parameter="select",
                        value=kwds[var_name],
                        options=[
                            str(s.filename)
                            for s in self.review_manager.settings.sources
                        ],
                    )
            return func_in(self, *args, **kwds)
        new_f.__name__ = func_in.__name__
        return new_f
    return check_accepts