Four components of logger

1. Loggers

2. processor

3. Formatter

4. Filter

class Test_log:
    def get_logger(self):
        # The log level ：debug info  warning error critical
        # The log level first depends on the logger , Then look at the log processor 
        #  Create a logger 
        self.logger = logging.getLogger("logger")
        self.logger.setLevel("DEBUG")

        if not self.logger.handlers:
            #  Create processor 
            sh = logging.StreamHandler()
            fh = logging.FileHandler("{}_log.txt".format(time.strftime("%Y_%m_%d_%H_%M_%S",time.localtime())))

            #  Create a formatter 
            fmt = logging.Formatter(fmt="%(asctime)s %(filename)s %(levelname)s %(message)s",datefmt="%Y/%m/%d_%H:%M:%S")
            sh.setFormatter(fmt)
            fh.setFormatter(fmt)

            self.logger.addHandler(sh)
            self.logger.addHandler(fh)

        return self.logger