| In axum a "handler" is an async function that accepts zero or more | |
| ["extractors"](crate::extract) as arguments and returns something that | |
| can be converted [into a response](crate::response). | |
| Handlers are where your application logic lives and axum applications are built | |
| by routing between handlers. | |
| [`debug_handler`]: https://docs.rs/axum-macros/latest/axum_macros/attr.debug_handler.html |