how do you send publish to specific joint using python3?

edit

In my terminal, it looks like this:

bwuk@robots:~/my_robot/my_robot_description$ ros2 topic echo /joint_states 
header:
  stamp:
    sec: 1629536818
    nanosec: 633569535
  frame_id: ''
name:
- joint_rear_left_wheel
- joint_rear_right_wheel
- joint_front_right_wheel
- joint_front_left_wheel
- head_attach
- head_attach2
position:
- 0.0
- 0.0
- 0.0
- 0.0
- 0.0
- 0.0
velocity: []
effort: []
---
header:
  stamp:
    sec: 1629536818
    nanosec: 656484369
  frame_id: ''
name:
- joint_rear_left_wheel
- joint_rear_right_wheel
- joint_front_right_wheel
- joint_front_left_wheel
- head_attach
- head_attach2
position:
- 0.0
- 0.0
- 0.0
- 0.0
- 0.0
- 0.0
velocity: []
effort: []
---

As you can see that joint_states has 6 joints inside. How do I run each joint inside the /joint_states?

I wanted to send like, for example, 5 m/s velocity to joint_front_left_wheel only so it can move in gazebo/rviz2.

How do I do that in python3?

Keywords: Foxy ubuntu 20.04 ros2 python python3 publisher joint one wheel single