localhost+port = default port

[vzong]

db = MySQLdb.connect(host="localhost", port=12345, user=mysql_user, passwd=mysql_password, db="configdb", charset='utf8', connect_timeout=10)
print(db.port) # 12345
but connect to default port 3306.

if host="127.0.0.1", port=12345
connect to 12345.