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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def init_logger(root_dir, name="train.log"):
 """Initialize a logger Parameters root_dir : str directory for saving log name : str name of logger Returns ------- logger : logging.Logger a logger """

    os.makedirs(root_dir, exist_ok=True)
    log_formatter = logging.Formatter("%(message)s")
    logger = logging.getLogger(name)
    file_handler = logging.FileHandler("{0}/{1}".format(root_dir, name), mode='w')
    file_handler.setFormatter(log_formatter)
    logger.addHandler(file_handler)
    console_handler = logging.StreamHandler()
    console_handler.setFormatter(log_formatter)
    logger.addHandler(console_handler)
    logger.setLevel(logging.INFO)
    return logger