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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 cnxml_to_html(cnxml_source):
 """Transform the CNXML source to HTML"""

    source = _string2io(cnxml_source)
    xml = etree.parse(source)
    # Run the CNXML to HTML transform
    xml = _transform('cnxml-to-html5.xsl', xml,
                     version='"{}"'.format(version))
    xml = XHTML_MODULE_BODY_XPATH(xml)
    return etree.tostring(xml[0])