How to use the @here/olp-sdk-dataservice-api.MetadataApi.getLayerVersions function in @here/olp-sdk-dataservice-api

catalogVersionRequest.withBillingTag(billingtag);
            }
            requestedCatalogVersion = await this.getLatestVersion(
                catalogVersionRequest
            ).catch(error => {
                latestVersionError = error;
                return undefined;
            });
            
            if (!requestedCatalogVersion) {
                return Promise.reject(`Failed to get the latest version with error: ${latestVersionError}`);
            }
        }

        let layerVersionsError: any;
        const layerVersions = await MetadataApi.getLayerVersions(builder, {
            version: requestedCatalogVersion,
            billingTag: request.getBillingTag()
        }).catch(err => {
            layerVersionsError = err;
            return undefined;
        });
        if (!layerVersions) {
            return Promise.reject(`Failed to get layerVersions with error: ${layerVersionsError}`);
        }

        return Promise.resolve(layerVersions.layerVersions);
    }