pub fn invert(&self) -> Self {
        let days = -self.days;
        let months = -self.months;
        let years = -self.years;
        Duration {
            days,
            months,
            years,
        }
    }
/// Inverts a duration by changing the sign on every part of the duration
Inverts a duration by changing the sign on every part of the duration
Inverts a duration by changing the sign on every part of the duration
pub fn invert(&self) -> Self {
        let days = -self.days;
        let months = -self.months;
        let years = -self.years;
        Duration {
            days,
            months,
            years,
        }
    }
pub fn invert ( & self ) -> Self { let days = - self . days ; let months = - self . months ; let years = - self . years ; Duration { days , months , years , } }
Inverts a duration by changing the sign on every part of the duration
Inverts a duration by changing the sign on every part of the duration
&self
&self