Chapter 5 : Error when launch file

Hi , i just did the chapter 5 OpenAI in moving cube robot , but when i started to launch , the Error was happened like this

the rosdep view is empty: call ‘sudo rosdep init’ and ‘rosdep update’
Traceback (most recent call last):
File “/home/user/catkin_ws/src/my_moving_cube_pkg/scripts/”, line 45, in
env = gym.make(‘MyMovingCubeOneDiskWalkEnv-v0’)
File “/usr/local/lib/python2.7/dist-packages/gym/envs/”, line 161, in make
return registry.make(id)
File “/usr/local/lib/python2.7/dist-packages/gym/envs/”, line 119, in make
env = spec.make()
File “/usr/local/lib/python2.7/dist-packages/gym/envs/”, line 86, in make
env = cls(*self._kwargs)
File “/home/user/catkin_ws/src/my_moving_cube_pkg/scripts/”, line 68, in init
super(MyMovingCubeOneDiskWalkEnv, self).init()
TypeError: init() takes exactly 2 arguments (1 given)
[movingcube_gym-1] process has died [pid 7927, exit code 1, cmd /home/user/catkin_ws/src/my_moving_cube_pkg/scripts/ __name:=movingcube_gym __log:=/home/user/.ros/log/27c8e82e-97e8-11ea-bac4-06c5091f5d92/movingcube_gym-1.log].
log file: /home/user/.ros/log/27c8e82e-97e8-11ea-bac4-06c5091f5d92/movingcube_gym-1
all processes on machine have died, roslaunch will exit
shutting down processing monitor…
… shutting down processing monitor complete

Can u help me please ? Thanks

This part of the error tells you that in line 68 of /home/user/catkin_ws/src/my_moving_cube_pkg/scripts/ you are only parsing 1 argument (which is ‘self’), but 2 are required. Meaning that you have to parse some variable when initializing that class. Check the MyMovingCubeOneDiskWalkEnv class to see, what the init function requires.