ListPortInfo.serial_number is an empty string when device's serial number includes a - hyphen.

[Qlexio]

I have a device which serial number is CCC-NNNNNNNN, when geting the comports the serial number is ''. I quickly checked and the regex for serial number in list_ports_windows is "^\w+$", so it does not get the serial numbers that include typographic characters other than _.

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This issue has been cloned from: pyserial#771