It is “built-in” as the name is part of python. However, Python runs top to bottom, rather than having a special entrypoint. So name is just a utility you can use in your design.

While it can be a good practice to define a main entrypoint, that’s more of a design decision and not hard rule. Many applications would not benefit from it because there is only one way to actually call the application to begin with.

Edit: Also not a dumb question. All programming languages have unique elements to them due to how they were envisioned and or developed over time (Pythons 30 years old)