helper method to change `paths` to absolute paths.
    Returns a `set` object
    `paths` can be either a single object or iterable

def to_absolute_paths(paths):
    """
    helper method to change `paths` to absolute paths.
    Returns a `set` object
    `paths` can be either a single object or iterable
    """
    abspath = os.path.abspath
    paths = return_set(paths)
    absolute_paths = {abspath(x) for x in paths}
    return absolute_paths