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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 xlsx_to_strio(xlsx_wb):
 """ convert xlwt Workbook instance to a BytesIO instance """

    _xlrd_required()
    fh = BytesIO()
    xlsx_wb.filename = fh
    xlsx_wb.close()
    # prep for reading
    fh.seek(0)
    return fh