code: def create_logger(log_file, name='logger', cmd=True):
      
      import logging
      logger = logging.getLogger(name)
      logger.setLevel(logging.DEBUG)
  
      # set format
      formatter = logging.Formatter('%(asctime)s | %(name)s | %(levelname)s | %(message)s',
                                    datefmt='%Y-%m-%d %H:%M:%S')
  
      # file handler
      fh = logging.FileHandler(log_file)
      fh.setLevel(logging.DEBUG)
      fh.setFormatter(formatter)
      logger.addHandler(fh)
  
      # cmd handler
      if cmd:
          ch = logging.StreamHandler()
          ch.setLevel(logging.DEBUG)
          ch.setFormatter(formatter)
          logger.addHandler(ch)
  
      return logger
docs: define a logger for your program
  
      parameters
      ------------
      log_file     file name of log
      name         name of logger
  
      example
      ------------
      logger = create_logger('example.log',name='logger',)
      logger.info('This is an example!')
      logger.warning('This is a warn!')