TypeError:字符串格式化过程中并非所有参数都已转换[MySQL DB connection]

Question

hostname = raw_input("Enter hostname : ")

connection = MySQLdb.connect (host = "localhost", user = "hawkhost_databas", passwd = "}MFkdDI6]#QX", db = "hawkhost_database")

cursor = connection.cursor ()

cursor.execute ("select User, Hostname, Password, Port from dbinfo where hostname=%s", (hostname))