wb = Workbook()
ws = wb.active
ws.title = 'Excel Using Openpyxl'
c = ws.cell(row=5, column=5)
c.value = 'Hi on 5,5'
out = StringIO.StringIO()
wb.save(out)
out.seek(0)
return send_file(out, mimetype=
    'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet',
    attachment_filename='xxl.xlsx', as_attachment=True)
how to output xlsx generated by Openpyxl to browser?