gazebo.launch

<?xml version="1.0"?>
<launch>
    <include file="$(find gazebo_ros)/launch/empty_world.launch">
        <arg name="verbose" value="true" />
        <arg name="world_name" value="$(find car_demo)/worlds/mcity.world" />
        <arg name="gui" value="true" />
    </include>
</launch>