Keymapping--prefixes for event-codes?

I’m currently working on retro-fitting my key-mapping module to handle Panda’s new input-device support.

Excluding axial inputs for the moment, my key-mapping fundamentally comes down to “accepting” various input-events.

So, when doing so for devices other than the keyboard or mouse, would it be advisable that I set a prefix for each individual device? (I’m concerned about the possibility of events “colliding”–having the same name, and so one overwriting the other.)

And if so, what would be a safe prefix to use? I don’t see an obviously-unique ID-value; the “serial_number” value might work, but I don’t know how reliable that is, especially as it’s noted that it may be empty.