roslaunch does not work, but rosrun does

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I want to run a python script using roslaunch instead of rosrun. It works perfectly with rosrun

My rosrun command is rosrun controller_msgs detect_l515_ros.py

My roslaunch file is

<launch>
    <node name="detect_l515_ros" pkg="controller_msgs" type="detect_l515_ros.py" output="screen">
        <param name="agnostic_nms"            value="false"/>
        <param name="augment"                 value="false"/>
        <param name="classes"                 value="None"/>
        <param name="conf_thres"              value="0.25"/>
        <param name="device"                  value=""/>
        <param name="exist_ok"                value="false"/>
        <param name="img_size"                value="640"/>
        <param name="iou_thres"               value="0.45"/>
        <param name="name"                    value="exp"/>
        <param name="project"                 value="runs/detect"/>
        <param name="save_conf"               value="False"/>
        <param name="save_txt"                value="False"/>
        <param name="source"                  value="data/images"/>
        <param name="update"                  value="False"/>
        <param name="view_img"                value="False"/>
        <param name="weights"                 value="best.pt"/>
    </node>
</launch>

The error is popped as : FileNotFoundError: [Errno 2] No such file or directory: 'requirements.txt'