下面的python代码通过MySQLdb模块链接mysql数据库，然后打开数据库，并通过sql语句查询mysql的版本号，最后关闭数据库连接

#!/usr/bin/python
 
import MySQLdb
 
# Open database connection
db = MySQLdb.connect("localhost","testuser","test123","TESTDB" )
 
# prepare a cursor object using cursor() method
cursor = db.cursor()
 
# execute SQL query using execute() method.
cursor.execute("SELECT VERSION()")
 
# Fetch a single row using fetchone() method.
data = cursor.fetchone()
 
print "Database version : %s " % data
 
# disconnect from server
db.close()