For this exercise check out the sections:
- [Error Handling](https://doc.rust-lang.org/book/ch09-02-recoverable-errors-with-result.html)
- [Generics](https://doc.rust-lang.org/book/ch10-01-syntax.html)

of the Rust Book.

or alternatively, check out the sections:
- [Result](https://doc.rust-lang.org/rust-by-example/error/result.html)
- [Boxing errors](https://doc.rust-lang.org/rust-by-example/error/multiple_error_types/boxing_errors.html)
  
of the Rust By Example Book.