def METHOD_NAME(
    self, codeloc: CodeLocation, exprs: bool = False
) -> Union[Set["Definition"], Set[Tuple["Definition", Optional[Any]]]]:
    """
    Retrieve all definitions that are used at a given location.
    :param codeloc: The code location.
    :return:        A set of definitions that are used at the given location.
    """
    if exprs:
        return self._uses_by_location.get(codeloc, set())
    return {item[0] for item in self._uses_by_location.get(codeloc, set())}