fn delete_account(&mut self, account_id: &Hash) -> Option<Account> {
        self.accounts.remove(account_id).map(|account| {
            self.accounts_len -= 1;
            account
        })
    }
/// returns the account that was deleted, or None if no account exists for specified account ID
returns the account that was deleted, or None if no account exists for specified account ID
returns the account that was deleted or None if no account exists for specified account ID
fn delete_account(&mut self, account_id: &Hash) -> Option<Account> {
        self.accounts.remove(account_id).map(|account| {
            self.accounts_len -= 1;
            account
        })
    }
fn delete_account ( & mut self , account_id : & Hash ) -> Option < Account > { self . accounts . remove ( account_id ) . map ( | account | { self . accounts_len -= 1 ; account } ) }
returns the account that was deleted, or None if no account exists for specified account ID
returns the account that was deleted or None if no account exists for specified account ID
&mut self
account_id
&Hash