import boto3
import pymysql
import sys

region = 'eu-west-1'
user = 'username'
password = 'password'
snapshot_name = 'snapshot'

source = boto3.client('rds', region_name=region)

def lambda_handler(event, context):
    try:
        dbs = source.describe_db_instances(DBInstanceIdentifier='new-db-instance')
        rds_host = dbs.get('DBInstances')[0].get('Endpoint').get('Address')
        print("%s")%(rds_host)
    except Exception as ex:
        print ex
        sys.exit()

    try:
        conn = pymysql.connect(host=rds_host, port=3306, user=user, passwd=password, db='mysql', connect_timeout=5)
    except Exception as ex:
        print ex
        sys.exit()
    with conn.cursor() as cur:
        cur.execute("some_SQL_script")
    cur.close()
    conn.close()

    try:
        source.delete_db_snapshot(DBSnapshotIdentifier=snapshot_name)
        source.delete_db_instance(DBInstanceIdentifier=db_instance,SkipFinalSnapshot=False,FinalDBSnapshotIdentifier=snapshot_name)
    except Exception as ex:
        print ex