Problem to run MAVProxy


I am new in the community. We are trying to run the tutorial to run MAVProxy and DroneKit

We follow exactly as mentioned by the tutorial (using Ubuntu), we run the initial script with code:

set moddebug 1
module load graph

Then we have the following output:

Connect /dev/ttyUSB0 source_system=255
Logging to mav.tlog
Running script /home/viviano/.mavinit.scr
-> set moddebug 1
-> module load graph
Loaded module graph

After that, we cannot run any command. All commands we try return no output, neither an error message. For example, when we try to run (only work from script, not from prompt), we have the output:

<droneapi.module.api.MPVehicle object at 0x7ff5b2f4bad0>

Get all vehicle attribute values:
Location: Location:lat=None,lon=None,alt=None,is_relative=False
Attitude: Attitude:pitch=None,yaw=None,roll=None
Velocity: [None, None, None]
-> module load graph
GPS: GPSInfo:fix=None,num_sat=None
Loaded module graph
Groundspeed: None
Airspeed: None
MAV> Mount status: [None, None, None]

Could anybody help us?

Best regards,
Alisson Brito