/lib/udev/rules.d/40-inputattach.rules is in inputattach 1:1.4.7-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 | # Attach Wacom W8001 devices
SUBSYSTEM=="tty", KERNEL=="ttyS[0-9]*", ATTRS{id}=="FUJ02e5", ACTION=="add|change", RUN+="/lib/udev/inputattach --daemon --baud 19200 --w8001 /dev/%k"
SUBSYSTEM=="tty", KERNEL=="ttyS[0-9]*", ATTRS{id}=="WACf00c", ACTION=="add|change", RUN+="/lib/udev/inputattach --daemon --baud 38400 --w8001 /dev/%k"
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