Python连接数据库

import pymysql

class DBconnection:
    connection = pymysql.connect(host='localhost',
                                 user='root',
                                 password='123456',
                                 db='seleniumdb',
                                 charset='utf8',
                                 cursorclass=pymysql.cursors.DictCursor)

    def get_list(self,fname):
        cur = self.connection.cursor()
        sql ="select e.etype,e.evalue from elementdata e where e.ename=%s"
        try:
            cur.execute(sql,fname)
            results = cur.fetchall()
            return results
        except:
            print("Error:unable to fetch data")
        self.connection.close()

    def get_ename(self,function):
        cur = self.connection.cursor()
        sql ="select e.ename, e.etype, e.evalue, e.eoperator,e.values from elementdata e where e.function=%s"
        try:
            cur.execute(sql,function)
            results = cur.fetchall()
            return results
        except:
            print("Error:unable to fetch data")
        self.connection.close()

    def getvalue(self,fname):
        elist =self.get_list(fname)
        edict = {}
        if len(elist)>1:
            print('元素获取有误')
        else:
            edict = elist[0]

        return edict
    # def ename_value(self,function):
    #     ename = self.get_ename(function)





# db =DBconnection()
# elist = db.get_ename('登陆')
# print(type(elist[0]))
# print(elist)
# dict =db.getvalue()
# print(type(dict))
# print(dict["etype"],dict["evalue"])