Support direct connect to a serial port
There are some cases that its just easier to have the ability to specify a serial port that should be used to get input/output for the job from. Today we use 'connection_command' and something like ser2net. However in some cases there can be races between when the serial port is available and the 'connect_command' is able to succeed.
So look at using pySerial as a solution to using serial ports directly.