NameError：名称“ cursor”未定义

我正在尝试连接mysql并更改信息，但不起作用。

main.py

import pymysql

def connect_setting():
    # Trying to connect
    db_connection = None
    try:
        db_connection = pymysql.connect(
        user='db', 
        passwd='password', 
        host='127.0.0.1', 
        db='test', 
        charset='utf8'
        )
       # If connection is not successful
    except:
        print("Can't connect to database")
        return 0
    # If Connection Is Successful
        print("Connected")

    # Making Cursor Object For Query Execution
        global cursor
        cursor = db_connection.cursor()


def get_off():

    sql = '''INSERT INTO  \` -100 \` '''

    cursor.execute(sql)
    db_connection.commit()

index.py

from main import get_off as sql

sql()

错误

raceback (most recent call last):
  File "/workspace/Kakao_points/index.py", line 3, in <module>
    sql()
  File "/workspace/Kakao_points/main.py", line 30, in get_off
    cursor.execute(sql)
NameError: name 'cursor' is not defined

我已经定义了游标，但我猜python在下一个def中没有得到信息。有人请帮助..？

问题来源：stackoverflow