How to change log level to debug in ROS2 Eloquent?

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This is part of my launch file. I am trying to change log level to debug but __log_level:=debug doesn't work. How can I do it? I have been looking in the documentation but I wasn't able to find this information.

launch_ros.actions.Node(
package='object_analytics_node', 
    node_executable='object_analytics_node',
    arguments=['--tracking', '--localization', '__log_level:=debug'],
    remappings=[
        ('/object_analytics/detected_objects', '/ros2_openvino_toolkit/detected_objects'),
        ('/object_analytics/rgb', camera_topic_image),
        ('/object_analytics/pointcloud', '/camera/depth/color/points')
    ], 
    output='screen'
),