python mysql database operation example, increasing the database row

Import pymysql 
Conn = pymysql.connect (Host = ' 127.0.0.1 ' , Port = 3306, = User ' the root ' , the passwd = ' 990 310 ' , DB = ' School ' , charset = ' UTF8 ' ) 
Cursor = conn.cursor ( ) 
L = [ 
    ( ' duck 1 ' , ' F ' , 2 ), 
    ( ' duck 2 ' , ' F ' , 2 ),
    ('鸭蛋3', '女', 2)
]
#r = cursor.execute('insert into student(sname,gender,class_id) values(%s,%s,%s)',(inp,'女',1))
r = cursor.executemany('insert into student(sname,gender,class_id) values(%s,%s,%s)',l)

conn.commit()
print(r)
cursor.execute('select * from class')
cursor.close()
conn.close()