How to start ros2 bag play from launch file?

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I would like to start a rosbag file from within a python launch file. How would it be possible to start the command line argument

$ ros2 bag play myfile.db3

within a python launch file. Thanks

My launchfile looks as the following:

from launch import LaunchDescription
from launch_ros.actions import Node

def generate_launch_description():
  ld = LaunchDescription()
  # ------------------------- Nodes ------------------------- #
  rosbag_play = (
    package='rosbag',
    executable='play',
    arguments= "--loop ~/path/to/myfile.db3",
    output='screen'
  )
  ...
  # -------------------------------------------------------- #
  ld.add_action(rosbag_play)
  ...
  return ld