fn has_only_jokers(&self) -> bool {
        for card in &self.0 {
            if *card != Joker {
                return false;
            }
        }
        true
    }
/// check if the sequence contains only jokers
check if the sequence contains only jokers
check if the sequence contains only jokers
fn has_only_jokers(&self) -> bool {
        for card in &self.0 {
            if *card != Joker {
                return false;
            }
        }
        true
    }
fn has_only_jokers ( & self ) -> bool { for card in & self . 0 { if * card != Joker { return false ; } } true }
check if the sequence contains only jokers
check if the sequence contains only jokers
&self
&self