The correct posture for operating MySQL in Python

pip install pymysql

pip install pymysql-x.x.x.tar.gz

import pymysql

def connect_wxremit_db():
    return pymysql.connect(host='10.123.5.28',
                           port=3306,
                           user='root',
                           password='root1234',
                           database='db_name',
                           charset='latin1')

def query_country_name(cc2):
    sql_str = ("SELECT Fcountry_name_zh"
                + " FROM t_country_code"
                + " WHERE Fcountry_2code='%s'" % (cc2))
    logging.info(sql_str)

    con = mysql_api.connect_wxremit_db()
    cur = con.cursor()
    cur.execute(sql_str)
    rows = cur.fetchall()
    cur.close()
    con.close()

    assert len(rows) == 1, 'Fatal error: country_code does not exists!'
    return rows[0][0]

def insert_file_rec(self, file_name, file_md5):
        con = mysql_api.connect_wxremit_db()
        cur = con.cursor()
        try:
            sql_str = ("INSERT INTO t_forward_file (Ffile_name, Ffile_md5)", 
                       + " VALUES ('%s', '%s')" % (file_name, file_md5))
            cur.execute(sql_str)
            con.commit()
        except:
            con.rollback()
            logging.exception('Insert operation error')
            raise
        finally:
            cur.close()
            con.close()

remit_ids = [('1234', 'CAD'), ('5678', 'HKD')]

con = mysql_api.connect_wxremit_db()
        cur = con.cursor()
        try:
                cur.executemany("INSERT INTO t_order (Fremit_id, Fcur_type, Fcreate_time"
                                                + " VALUES (%s, %s, now())", new_items)
                assert cur.rowcount == len(remit_ids), 'my error message'
                con.commit()
        except Exception as e:
                con.rollback()
                logging.exception('Insert operation error')
        finally:
                cur.close()
                con.close()

    def update_refund_trans(self, remit_id):
        con = mysql_api.connect_wxremit_db()
        cur = con.cursor()
        try:
            sql_str = ("SELECT Fremit_id"
                       + " FROM t_wxrefund_trans"
                       + " WHERE Fremit_id='%s'" % remit_id
                       + " FOR UPDATE")
            logging.info(sql_str)

            cur.execute(sql_str)
            assert cur.rowcount == 1, 'Fatal error: The wx-refund record be deleted!'

            sql_str = ("UPDATE t_wxrefund_trans"
                        + " SET Fcheck_amount_flag=1"
                        + ", Fmodify_time=now()"
                        + " WHERE Fremit_id='%s'" % remit_id
            logging.info(sql_str)
            cur.execute(sql_str)

            assert cur.rowcount == 1, 'The number of affected rows not equal to 1'
            con.commit()
        except:
            con.rollback()
            logging.exception('Update operation error')
            raise
        finally:
            cur.close()
            con.close()