import traceback
def clac(a,b):
    return a/b

def main():
    money = input("輸入多少錢：")
    months = input("還幾個月：")
    try:
        res = clac(int(money),int(months))
    except ZeroDivisionError as e:
        print('還款的月數不能小于1，',e)
        # traceback.print_exc() #可以輸出報錯的詳細信息,哪行錯誤
    except ValueError as e: #ValueError可以先運行一次后，在錯誤結果中獲取
        print('輸入必須是整數%s',e)
    # except Exception as e: #捕捉到所有異常，當不確定是哪種異常時，可以使用
    #     print('未知錯誤！',e)
    else:#沒有錯的情況下走else
        print('每月應該還%s' % res)

main()

import pymysql
def main2(sql):
    try :
        conn = pymysql.connect(host = '122.33.22.33',user = 'root',password = '123456',port = '3306')
    except Exception as e:
        print('shujukulianjiebuliao,%s'%e)
    else:
        cur = conn.cursor()
        try:
            cur.execute(sql)
        except Exception as e:
            print('sql error：%s,sql = %s'%(e,sql))
        else:
            res = cur.fetchall()
            return res
        finally: #不管有沒有捕捉到異常，都會走到這里
            cur.close()
            conn.close()

import requests
def req():
    r = requests.get('http://api.nnzhp.cn/api/user/all_stu',headers={"Referer":"http://api.nnzhp.cn/"})
    if len(r.json()['stu_info'])<0:
        pass
    else:
        raise Exception('接口無返回數據') #主動拋出異常

req()