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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 delete_tags(self, arg):
 """Removes html-tags from extracted data. :param arg: A string, the string which shall be cleaned :return: A string, the cleaned string """


        if len(arg) > 0:
            raw = html.fromstring(arg)
            return raw.text_content().strip()

        return arg