code: def using_config(_func=None):
      
      def decorator(func):
          @wraps(func)
          def inner_dec(*args, **kwargs):
              g = func.__globals__
              var_name = 'config'
              sentinel = object()
  
              oldvalue = g.get(var_name, sentinel)
              g[var_name] = apps.get_app_config('django_summernote').config
  
              try:
                  res = func(*args, **kwargs)
              finally:
                  if oldvalue is sentinel:
                      del g[var_name]
                  else:
                      g[var_name] = oldvalue
  
              return res
          return inner_dec
  
      if _func is None:
          return decorator
      else:
          return decorator(_func)
docs: This allows a function to use Summernote configuration
      as a global variable, temporarily.