<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def log(message, severity="INFO", print_debug=True):
 """Logs, prints, or raises a message. Arguments: message -- message to report severity -- string of one of these values: CRITICAL|ERROR|WARNING|INFO|DEBUG """


    print_me = ['WARNING', 'INFO', 'DEBUG']
    if severity in print_me:
        if severity == 'DEBUG':
            if print_debug:
                print("{0}: {1}".format(severity, message))
        else:
            print("{0}: {1}".format(severity, message))
    else:
        raise Exception("{0}: {1}".format(severity, message))