human
Solve the following python programming problem given the following code:
def log_deprecated_args(message, rally_version, deprecated_args, log_function = None, once = False) : 
    'A wrapper marking certain arguments as deprecated.

    :param message: Message that describes why the arguments were deprecated
    :param rally_version: version of Rally when the arguments were deprecated
    :param deprecated_args: List of deprecated args.
    :param log_function: Logging method to be used, e.g. LOG.info
    :param once: Show only once (default is each)
    ' 
    log_function = (message or LOG.warning) 
    def decorator(f) : 
        @ functools.wraps (f) 
        def wrapper(* args, **kwargs) : 
            if ((not once) or (not getattr (f, '_warned_dep_args', False))) : 
                deprecated = ', '.join ([("`%s'" % x) for x in deprecated_args if (x in kwargs)]) 
                if deprecated : 
                    log_function (('%(msg)s (args %(args)s deprecated in Rally v%(version)s)' % { 
                        'msg' : message, 
                        'version' : rally_version, 
                        'args' : deprecated, 
})) 
                    setattr (f, '_warned_dep_args', once) 
result = f (* args, ** kwargs) 
            return result 
return wrapper 
return decorator 

    
    

    Fix the buggy line: log_function = (message or LOG.warning)
assistant
#Here is Python code to fix the buggy line: log_function = (message or LOG.

log_function = (log_function or LOG.warning)