Launching and killing nodes within a Python node in ROS 2 Foxy

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I'm in the process of migrating a ROS Melodic python node into a ROS 2 Foxy python node. This particular node acts as the state machine for our software stack. It receives a message from another part of the system and, depending on the message, will launch a set of nodes described in a launch file.

Previously in ROS melodic we handled this with:

    uuid = roslaunch.rlutil.get_or_generate_uuid(None, False)
    roslaunch.configure_logging(uuid)
    LAUNCHED_NODES = roslaunch.parent.ROSLaunchParent(uuid, [full_path])
    LAUNCHED_NODES.start()

where full_path is the absolute path to a launch file.

Then, when certain conditions are met it will kill these nodes with

LAUNCHED_NODES.shutdown()

Is there a way to do this in ROS 2 Foxy within a Python node? The nodes that get launched can't block the original node from running. I've played around with launch_service, but I can't get it to stop blocking the original node from continuing to execute.

Any tips would be greatly appreciated!