How to use the graphql-auth-transformer.ModelAuthTransformer function in graphql-auth-transformer

new DynamoDBModelTransformer(),
    new ModelConnectionTransformer(),
    new VersionedModelTransformer(),
    new DefaultValueTransformer()
]

// Only insert certain plugins if needed, otherwise they pollute the cloudformation
// for no good reason.
// We determine if needed with a simple string search for the directive string
function conditionalInsertDirectivePlugin(plugin, searchString){
    if (schema.indexOf(searchString) >= 0) {
        transformers.push(plugin)
    }
}

conditionalInsertDirectivePlugin(new ModelAuthTransformer(), '@auth');
conditionalInsertDirectivePlugin(new SearchableModelTransformer(), '@searchable');

// console.log(process.argv)
const transformer = new GraphQLTransform({
    transformers: transformers
})

const cfdoc = transformer.transform(schema);
console.log(JSON.stringify(cfdoc, null, 2))

return new CustomTransformer();
        } else if (typeof CustomTransformer === 'object') {
          return CustomTransformer;
        }

        throw new Error("Custom Transformers' default export must be a function or an object");
      })
      .filter(customTransformer => customTransformer);

    if (customTransformers.length > 0) {
      transformerList.push(...customTransformers);
    }

    // TODO: Build dependency mechanism into transformers. Auth runs last
    // so any resolvers that need to be protected will already be created.
    transformerList.push(new ModelAuthTransformer({ authConfig }));

    return transformerList;
  };
}