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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_parent(root):
 """Returns root element for a list. :Args: root (Element):
 lxml element of current location :Returns: lxml element representing list """


    elem = root

    while True:
        elem = elem.getparent()

        if elem.tag in ['ul', 'ol']:
            return elem