Shadows name xyz from outer scope

The warning is about the potential danger you are introducing by re-using these names at inner scopes. It can cause you to miss a bug. For example, consider this

def sample_func(*args):
    smaple = sum(args) # note the misspelling of `sample here`
    print(sample * sample)

if __name__ == "__main__":
    for sample in range(1, 5):
        sample_func()

Because you used the same name, your misspelling inside the function does not cause an error.

When your code is very simple, you will get away with this type of thing with no consequences. But it’s good to use these “best practices” in order to avoid mistakes on more complex code.