pub fn schedule_leave<T: Config>(&mut self) -> Result<(RoundIndex, RoundIndex), DispatchError> {
self.lowest_bottom_delegation_amount = bottom_delegations.lowest_delegation_amount().into();
/// and when increasing the bond lock will also ensure that the account has enough free balance.
/// `additional_required_balance` should reflect the change to the amount that should be locked if
/// positive, 0 otherwise (e.g. `min(0, change_in_total_bond)`). This is necessary because it is
B: Copy + sp_std::ops::Add<Output = B> + sp_std::ops::Sub<Output = B> + From<u32> + PartialOrd,
B: Copy + sp_std::ops::Add<Output = B> + sp_std::ops::Sub<Output = B> + From<u32> + PartialOrd,