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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 _add_log_file(filename):
 """Create a `phy.log` log file with DEBUG level in the current directory."""

    handler = logging.FileHandler(filename)

    handler.setLevel(logging.DEBUG)
    formatter = _Formatter(fmt=_logger_fmt,
                           datefmt='%Y-%m-%d %H:%M:%S')
    handler.setFormatter(formatter)
    logging.getLogger().addHandler(handler)