How to include another package's launchfile in my launchfile ?

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Hi all,

I got a problem. I don't see a way to include an another launchfile from a launchfile that is not in the current package. I want to add arguments to this launchfile

Example :

To include an other launchfile I do this :

IncludeLaunchDescription( PythonLaunchDescriptionSource([ThisLaunchFileDir(), '/gzserver.launch.py']), launch_arguments={'world': 'PATH'}.items(),

I'm not able to find a substitution to (in my example) the package gazebo_ros. Is it possible ?

An other question, how can I put multiple argument on this include like :

IncludeLaunchDescription( PythonLaunchDescriptionSource([ThisLaunchFileDir(), '/gzserver.launch.py']), launch_arguments={'world': 'PATH','verbose':'true'}.items(),

Thanks a lot for your answer.

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