Handling errors as exceptions

• Only need to explicitly check for it at the level where we know what to do with the problem.
• But: Do we want our pacemaker to stop totally after missing one beat? Probably not. Or better yet: not when it is in production.

main()
    ...
    try:
        ...
        result = do_something(filename)
        do_something_else(result)
    except Exception:
        decide_what_to_do()

    always_happens()