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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 aloha_to_etree(html_source):
 """ Converts HTML5 from Aloha editor output to a lxml etree. """

    xml = _tidy2xhtml5(html_source)
    for i, transform in enumerate(ALOHA2HTML_TRANSFORM_PIPELINE):
        xml = transform(xml)
    return xml