有一个数据框mortgage_data，其中列名称为mortgage_amount 和month（按升序排列）
mortgage_amount_paid = 1000
抵押数据：
name mortgage_amount month
mark 400 1
mark 500 2
mark 200 3
如何在数据框中mortgage_amount使用逐行按升序或月份扣除和更新，并添加一列，如果抵押贷款金额已完全扣除该金额，则添加为“是”，如果不是这样，则添加为“否”mortgage_amount_paidpaid_status
如果mortgage_amount_paid = 1000
抵押数据：
name mortgage_amount month mortgage_amount_updated paid_status
mark 400 1 0 full
mark 500 2 0 full
mark 200 3 100 partial
前任：
如果mortgage_amount_paid = 600
抵押数据：
name mortgage_amount month mortgage_amount_updated paid_status
mark 400 1 0 full
mark 500 2 300 partial
mark 200 3 200 zero
尝试过这个：
mortgage_amount_paid = 600
# amount …