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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 build_xlsx_response(wb, title="report"):
 """ Take a workbook and return a xlsx file response """

    title = generate_filename(title, '.xlsx')
    myfile = BytesIO()
    myfile.write(save_virtual_workbook(wb))
    response = HttpResponse(
        myfile.getvalue(),
        content_type='application/vnd.openxmlformats-officedocument.spreadsheetml.sheet')
    response['Content-Disposition'] = 'attachment; filename=%s' % title
    response['Content-Length'] = myfile.tell()
    return response