This information is spread across multiple websites and still does not give a direct solution.
I changed a print statement and was trying to see if just running sim_vehicle.py would build and run (ArduCopter) code for me. Then I tried building…
./waf configure --board sitl --debug
then ran sim_vehicle.py -v ArduCopter --console --map and still cant see the changed print statement. Its so frustrating trying to find simple information for hours.