def opv(d, func, *args):
    """
    Apply func to all values of a dictionary.

    :param d: A dictionary.
    :param func: Callable accepting a value of `d` as first parameter.
    :param args: Additional positional arguments to be passed to `func`.
    :return: `dict` mapping the keys of `d` to the return value of the function call.
    """
    return {i: func(v, *args) for i, v in d.items()}