fix linting errors

littlebot_control/launch/spawn_diffdriver_controller.launch.py

@@ -1,7 +1,5 @@
-import os
 from launch_ros.actions import Node
 from launch import LaunchDescription
-from launch.launch_description_sources import PythonLaunchDescriptionSource
 from launch.actions import RegisterEventHandler
 from launch.event_handlers import OnProcessExit
 
@@ -10,24 +8,25 @@ def generate_launch_description():
     joint_state_broadcaster_spawner = Node(
         package="controller_manager",
         executable="spawner",
-        arguments=["joint_state_broadcaster", "--controller-manager", "/controller_manager"],
+        arguments=["joint_state_broadcaster",
+                   "--controller-manager", "/controller_manager"],
     )
 
     robot_controller_spawner = Node(
         package="controller_manager",
         executable="spawner",
-        arguments=["littlebot_velocity_controller", "--controller-manager", "/controller_manager"],
+        arguments=["littlebot_velocity_controller", "--controller-manager",
+                   "/controller_manager"],
     )
 
     rviz_node = Node(
         package="rviz2",
         executable="rviz2",
         name="rviz2",
         output="log",
-        # arguments=["-d", rviz_config_file],
     )
 
-    delay_robot_controller_spawner_after_joint_state_broadcaster_spawner = RegisterEventHandler(
+    delay_robot_controller_after_joint_state_spawner = RegisterEventHandler(
         event_handler=OnProcessExit(
             target_action=joint_state_broadcaster_spawner,
             on_exit=[robot_controller_spawner],
@@ -41,9 +40,7 @@ def generate_launch_description():
     )
 
     return LaunchDescription([
-        # control_node,
         joint_state_broadcaster_spawner,
-        delay_robot_controller_spawner_after_joint_state_broadcaster_spawner,
+        delay_robot_controller_after_joint_state_spawner,
         delay_rviz_after_robot_controller
-
     ])