pub fn level21() -> Nil

pub fn level22() -> Nil

pub fn level23() -> Nil

pub fn level24() -> Nil

pub fn level25() -> Nil

pub fn level31() -> Nil

pub fn level32() -> Nil

pub fn level33() -> Nil

pub fn level34() -> Nil

pub fn level38() -> Nil

pub fn level41() -> Nil

pub fn level47() -> Nil

pub fn library_eval(expr: String) -> Result(String, String)

pub fn server_eval(expr: String) -> String