[Docker] error in build on arch linux

[Horki]

Inside Docker on arch linux i have an error when launching styx

(874) wsgi starting up on http://0.0.0.0:4567
(874) accepted ('172.17.0.1', 37680)
message handler error
Traceback (most recent call last):
  File "/usr/local/lib/python2.7/dist-packages/engineio/server.py", line 544, in _trigger_event
    return self.handlers[event](*args)
  File "/usr/local/lib/python2.7/dist-packages/socketio/server.py", line 509, in _handle_eio_message
    self._handle_event(sid, pkt.namespace, pkt.id, pkt.data)
  File "/usr/local/lib/python2.7/dist-packages/socketio/server.py", line 448, in _handle_event
    self._handle_event_internal(self, sid, data, namespace, id)
  File "/usr/local/lib/python2.7/dist-packages/socketio/server.py", line 451, in _handle_event_internal
    r = server._trigger_event(data[0], namespace, sid, *data[1:])
  File "/usr/local/lib/python2.7/dist-packages/socketio/server.py", line 480, in _trigger_event
    return self.handlers[namespace][event](*args)
  File "/capstone/ros/src/styx/server.py", line 44, in control
    bridge.publish_controls(data)
  File "/capstone/ros/src/styx/bridge.py", line 145, in publish_controls
    self.publishers['steering_report'].publish(self.create_steer(steering))
  File "/capstone/ros/src/styx/bridge.py", line 102, in create_steer
    st.steering_wheel_angle_cmd = val * math.pi/180.
AttributeError: 'SteeringReport' object has no attribute 'steering_wheel_angle_cmd'
message handler error