'Append a new ancestor path to this multi-path
@param path: the ancestor path'

def append(self, path):

    Path = self.Path
    if isinstance(path, Path):
        path = path.nodes
    else:
        path = Path(path).nodes
    multipath = None
    paths = self.__normalize(path)
    append = self.paths.append
    for p in paths:
        p = Path(p)
        if (not (self & p)):
            append(p)
            multipath = self
    return multipath
