Gazebo 7.8.1 Problem with turtlebot spawn

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Hello all!

I updated my Gazebo version to 7.8.1 and ros-kinetic in Virtual Box with Ubuntu 16.04 but now I have a problem with turtlebot3 spawn model: The git source is here:

https://github.com/ROBOTIS-GIT/turtlebot3

https://github.com/ROBOTIS-GIT/turtlebot3_simulations

If you execute this command

roslaunch turtlebot3_gazebo turtlebot3_empty_world.launch

You can get such mistake:

Traceback (most recent call last):
  File "/opt/ros/kinetic/lib/gazebo_ros/spawn_model", line 26, in <module>
    from gazebo_ros import gazebo_interface
  File "/opt/ros/kinetic/lib/python2.7/dist-packages/gazebo_ros/gazebo_interface.py", line 9, in <module>
    from gazebo_msgs.msg import *
ImportError: No module named msg
[spawn_urdf-5] process has died [pid 29853, exit code 1, cmd /opt/ros/kinetic/lib/gazebo_ros/spawn_model -urdf -model turtlebot3_burger -x -2.0 -y -0.5 -z 0.0 -param robot_description __name:=spawn_urdf __log:=/home/student/.ros/log/7f3649f4-045a-11e8-9a27-0800274d83cf/spawn_urdf-5.log].
log file: /home/student/.ros/log/7f3649f4-045a-11e8-9a27-0800274d83cf/spawn_urdf-5*.log
[ INFO] [1517164737.844817246]: Finished loading Gazebo ROS API Plugin.
[ INFO] [1517164737.847707091]: waitForService: Service [/gazebo/set_physics_properties] has not been advertised, waiting...

The world is lunching but the robot model is absent. But before gazebo update I created my one world (in Gazebo 1.9) based on turtlebot3_empty_world and from saved copy I can launch the robot spawn model but I can't any world info like gazebo/model_states and gazebo/link_states .

I saw the same mistake here, but there was no answer there.