'''python 使用数据库-封装'''import pymysqlclass TestMysql(object):    def __init__(self):        self.a = None        ##定义一个字典        dbConfig = {            "host": "192.168.48.136",            "port": 3306,            "user": "chen",            "passwd": "123456",            "db": "test"        }    def get_connect(self):        if self.a == None:            # 函数传参 传入字典需要加**            conn = pymysql.connect(**self.dbConfig)            self.a = conn    # 使用时不再建立新的链接，只需要使用已有的    def select(self):        self.get_connect()        print("select")    def update(self):        self.get_connect()        print("update")def main():    testMysql = TestMysql()    testMysql.select()if __name__ == '__main__':    main()