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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 configure_logger(stream_level='DEBUG', debug_file=None):
 """Configure logging for cookiecutter. Set up logging to stdout with given level. If ``debug_file`` is given set up logging to file with DEBUG level. """

    # Set up 'cookiecutter' logger
    logger = logging.getLogger('cookiecutter')
    logger.setLevel(logging.DEBUG)

    # Remove all attached handlers, in case there was
    # a logger with using the name 'cookiecutter'
    del logger.handlers[:]

    # Create a file handler if a log file is provided
    if debug_file is not None:
        debug_formatter = logging.Formatter(LOG_FORMATS['DEBUG'])
        file_handler = logging.FileHandler(debug_file)
        file_handler.setLevel(LOG_LEVELS['DEBUG'])
        file_handler.setFormatter(debug_formatter)
        logger.addHandler(file_handler)

    # Get settings based on the given stream_level
    log_formatter = logging.Formatter(LOG_FORMATS[stream_level])
    log_level = LOG_LEVELS[stream_level]

    # Create a stream handler
    stream_handler = logging.StreamHandler(stream=sys.stdout)
    stream_handler.setLevel(log_level)
    stream_handler.setFormatter(log_formatter)
    logger.addHandler(stream_handler)

    return logger