https://github.com/nutechsoftware/alarmdecoder/issues/39

and they had pyserial hard coded to 2.7, which was python2
only..

The pinned version of alarmdecoder is because of this commit:
02312961a2

In my test data, from a real device conencted to a real system, the new
library doesn't work...  Likely there was a firmware update that changed
this behavior, but the code doesn't handle the older firmware..  This
may change w/ new devices, but this makes all the tests pass now...