Traceback (most recent call last): File "<python-input-0>", line 9, in <module> listener = mouse.Listener(on_move=lambda x, y: None, on_click=on_click) ^^^^^^^^ NameError: name 'on_click' is not defined >>> i got that error with that script

The error message indicates that the variable `on_click` is not defined. This is because you're trying to use it as a function before it's been defined.

Here's a simple example of how you can use the `pynput` library to create a mouse listener that logs mouse clicks:

```python
from pynput import mouse

def on_click(x, y, button, pressed):
    """Callback function for mouse click events."""
    if pressed:
        print(f'Mouse {button} pressed at ({x}, {y})')
    else:
        print(f'Mouse {button} released at ({x}, {y})')

def main():
    """Main function to create and start the mouse listener."""
    listener = mouse.Listener(on_move=None, on_click=on_click)
    listener.start()
    listener.join()

if __name__ == "__main__":
    main()
```

In this script, `on_click` is a function that takes four arguments: `x` and `y` (the coordinates of the mouse click), `button` (the mouse button that was clicked), and `pressed` (a boolean indicating whether the button was pressed or released).

When you run this script, it will start listening for mouse events and print a message whenever a mouse button is pressed or released.

Note that you'll need to install the `pynput` library first by running `pip install pynput` in your terminal.