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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_ms_item(xml, service, parent_id):
 """Return the music service item that corresponds to xml. The class is identified by getting the type from the 'itemType' tag """

    cls = MS_TYPE_TO_CLASS.get(xml.findtext(ns_tag('ms', 'itemType')))
    out = cls.from_xml(xml, service, parent_id)
    return out