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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 report_xml():
 """cr-xml Usage: cr-xml <session-file> Print an XML formatted report of test results for continuos integration systems """

    arguments = docopt.docopt(report_xml.__doc__, version='cr-rate 1.0')
    with use_db(arguments['<session-file>'], WorkDB.Mode.open) as db:
        xml_elem = _create_xml_report(db)
        xml_elem.write(
            sys.stdout.buffer, encoding='utf-8', xml_declaration=True)