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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 load_log(args):
 """Load a `logging.Logger` object. Arguments --------- args : `argparse.Namespace` object Namespace containing required settings: {`args.debug`, `args.verbose`, and `args.log_filename`}. Returns ------- log : `logging.Logger` object """

    from astrocats.catalog.utils import logger

    # Determine verbosity ('None' means use default)
    log_stream_level = None
    if args.debug:
        log_stream_level = logger.DEBUG
    elif args.verbose:
        log_stream_level = logger.INFO

    # Create log
    log = logger.get_logger(
        stream_level=log_stream_level, tofile=args.log_filename)
    log._verbose = args.verbose
    log._debug = args.debug
    return log