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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def commonancestors(*nodes):
 """ Determine common ancestors of `nodes`. (Node('/Udo'), Node('/Udo/Dan')) (Node('/Udo'),) (Node('/Udo'), Node('/Udo/Dan')) () """

    ancestors = [node.ancestors for node in nodes]
    common = []
    for parentnodes in zip(*ancestors):
        parentnode = parentnodes[0]
        if all([parentnode is p for p in parentnodes[1:]]):
            common.append(parentnode)
        else:
            break
    return tuple(common)