By default, `r` threw exceptions whenever the exit status was not 0. However, in some scenarios the caller is ok with some exit statuses. For example, when the caller wants to stop a systemd unit if it exists. In which case, it is ok if the exit status is 5. This change adds the `expect:` parameter to `r` to allow for that: ``` def r(commandline, stdin: "", expect: [0]) ```