raise

raise Exception(msg)

try...except...as...

try:
    code block
except Exception as err:
    error handling

traceback.format_exc()

• convert traceback stack info to be a string

assert condition, message

• Python -O option will disable assertions

logging module

import logging
logging.disable（logging.CRITICAL）
logging.basicConfig(level=logging.DEBUG, format=' %(asctime)s - %(levelname)s - %(message)s')
logging.basicConfig(filename='myProgramLog.txt', level=logging.DEBUG, 
                    format='(asctime)s - %(levelname)s - %(message)s')
logging.debug('Start of program')