How to use the n8n-core.Credentials function in n8n-core

type: incomingData.type,
				},
			} as FindOneOptions;

			const checkResult = await Db.collections.Credentials!.findOne(findQuery);
			if (checkResult !== undefined) {
				throw new ResponseHelper.ResponseError(`Credentials with the same type and name exist already.`, undefined, 400);
			}

			const encryptionKey = await UserSettings.getEncryptionKey();
			if (encryptionKey === undefined) {
				throw new Error('No encryption key got found to encrypt the credentials!');
			}

			// Encrypt the data
			const credentials = new Credentials(incomingData.name, incomingData.type, incomingData.nodesAccess);
			credentials.setData(incomingData.data, encryptionKey);
			const newCredentialsData = credentials.getDataToSave() as unknown as ICredentialsDb;

			// Add special database related data
			newCredentialsData.updatedAt = this.getCurrentDate();

			// Update the credentials in DB
			await Db.collections.Credentials!.update(id, newCredentialsData);

			// We sadly get nothing back from "update". Neither if it updated a record
			// nor the new value. So query now the hopefully updated entry.
			const responseData = await Db.collections.Credentials!.findOne(id);

			if (responseData === undefined) {
				throw new ResponseHelper.ResponseError(`Credentials with id "${id}" could not be found to be updated.`, undefined, 400);
			}

}

			const result = await Db.collections.Credentials!.findOne(req.params.id);

			if (result === undefined) {
				return result;
			}

			let encryptionKey = undefined;
			if (req.query.includeData === true) {
				encryptionKey = await UserSettings.getEncryptionKey();
				if (encryptionKey === undefined) {
					throw new Error('No encryption key got found to decrypt the credentials!');
				}

				const credentials = new Credentials(result.name, result.type, result.nodesAccess, result.data);
				(result as ICredentialsDecryptedDb).data = credentials.getData(encryptionKey!);
			}

			(result as ICredentialsDecryptedResponse).id = result.id.toString();

			return result as ICredentialsDecryptedResponse;
		}));