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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 get_ancestor_class_names(mention):
 """Return the HTML classes of the Mention's ancestors. If a candidate is passed in, only the ancestors of its first Mention are returned. :param mention: The Mention to evaluate :rtype: list of strings """

    span = _to_span(mention)
    class_names = []
    i = _get_node(span.sentence)
    while i is not None:
        class_names.insert(0, str(i.get("class")))
        i = i.getparent()
    return class_names