def genericDescendant(path, segments):
    """
    Retrieve a child or child's child of the given path.

    :param iterable segments: A sequence of path segments as L{str} instances.

    :return: A L{FilePath} constructed by looking up the C{segments[0]} child
             of this path, the C{segments[1]} child of that path, and so on.
    """
    for name in segments:
        path = path.child(name)
    return path
