Python code using ROS in a Docker container

Question

I am a beginner with ROS and am trying to run some Node Listener/talker running a really simple code in python, using ROS in a Docker container.

I am following the guide described in: https://hub.docker.com/_/Ros

I have this structure:

./
    Dockerfile
    docker-compose.yml
    ./teste/
            listener.py

My current goal is to pass the code Listener.py and run in a Node Listener, running as a service container.

My Dockerfile is:

FROM ros:foxy        
 # install ros package 
    RUN apt-get update && apt-get install -y \
              ros-${ROS_DISTRO}-demo-nodes-cpp \
              ros-${ROS_DISTRO}-demo-nodes-py && \
            rm -rf /var/lib/apt/lists/*
        
# launch ros package

CMD ["ros2", "launch", "demo_nodes_cpp", "talker_listener.launch.py"]

My file Docker-Compose.yml is:

version: '3'

services:
  talker:
    build: ./
    command: ros2 run demo_nodes_py talker

  listener:
    build: ./
    environment:
      - "PYTHONUNBUFFERED=1"
    volumes:
      - ./teste:/teste
    command: ros2 run demo_nodes_py listener

volumes:
  teste:

With this standard code, the two services run the Listener/talker of the original Ros examples, but I want to run my own python code. How do I do that? Even if the listener service can access the Listener.py code (via ./test) if I open a shell and try to run it, the ros2 run command is not recognized.

The ros2 command is not recognized if I open a terminal, but by the cmd command in Dockerfile, with the code talker_listener.launch.py, it works.

I was able to run the setup.sh via "/bin/bash source /opt/Ros/Foxy/setup.bash". Still, I cannot execute the ros2 commands. I used "python3 /test/Listener.py", but I got the bug:

ModuleNotFoundError: No module named 'rospy'

As this is possible, if when I run the default command option (ros2 run demo_nodes_py Listener, via Dockerfile) and it works?

What am I doing wrong? Should I do something first to make my python code work in ros2? Any ideas?

Thank you!