I have used serial.tools.list_ports.comports() to find an Arduino by looking for 'Arduino' in the device description. When I use it with the Teensy 3.2 on Win 10, the description of the device doesn't include the word 'Teensy'. It's description is u'USB Serial Device (COM3)' with manufacturer 'Microsoft'. So I don't know how to find the Teensy port.