Assistant: 
User: 
    Please analyze the following code file and determine whether it belongs to any of the provided modules based on the listed module descriptions.
    Note that the provided list of modules may not be exhaustive, and some files may not belong to any of the modules. 
    If the code belongs to a module, Only output the module name, without any explanation or additional information; otherwise, return 'None' if it does not belong to any module.

    Modules : {
        "UI": "Handles the front-end user interface, consisting of HTML, CSS, and JavaScript files generated by the Angular framework. It processes user requests and interacts with the server using AJAX for data retrieval and client-side interactions."
"Test Driver": "Facilitates automated regression testing and handles transmission of test data in JSON format. It performs Java testing using TestNG and JavaScript unit-testing with Jest. It also sets up a simulated web server for servlet-level tests and automates end-to-end testing using Selenium Java."
"Logic": "Manages the business logic of TEAMMATES, including handling relationships between entities, managing transactions, input value sanitization, access control rights, and interfacing with GAE-provided or third-party APIs."
"Storage": "Performs CRUD operations on data entities, validation of data, and abstraction of GQL queries, hiding the complexities of datastore from the Logic component."
"Common": "Contains utility classes, custom exceptions, and data transfer objects used across the entire application for easy consolidation and transfer of structured data."
"E2E": "Handles end-to-end testing and load & performance testing, providing helpers, abstractions of browser pages, and test cases for E2E tests and L&P tests."
"Client": "Contains scripts for administrative tasks, such as migrating data to a new schema and calculating statistics. This module connects directly to the application back-end for administrative purposes."
    }

    Code: package teammates.storage.api; /** * Base class for all classes performing CRUD operations against the database. * * @param <E> Specific entity class * @param <A> Specific attributes class */ abstract class EntitiesDb<E extends BaseEntity, A extends EntityAttributes<E>> { /** * Error message when trying to create entity that already exist. */ static final String ERROR_CREATE_ENTITY_ALREADY_EXISTS = "Trying to create an entity that exists: %s"; /** * Error message when trying to update entity that does not exist. */ static final String ERROR_UPDATE_NON_EXISTENT = "Trying to update non-existent Entity: "; /** * Info message when entity is not saved because it does not change. */ static final String OPTIMIZED_SAVING_POLICY_APPLIED = "Saving request is not issued because entity %s does not change by the update (%s)"; static final Logger log = Logger.getLogger(); /** * Creates the entity in the database. * * @return created entity * @throws InvalidParametersException if the entity to create is invalid * @throws EntityAlreadyExistsException if the entity to create already exists */ public A createEntity(A entityToCreate) throws InvalidParametersException, EntityAlreadyExistsException { return createEntity(entityToCreate, true); } private A createEntity(A entityToAdd, boolean shouldCheckExistence) throws InvalidParametersException, EntityAlreadyExistsException { assert entityToAdd != null; entityToAdd.sanitizeForSaving(); if (!entityToAdd.isValid()) { throw new InvalidParametersException(entityToAdd.getInvalidityInfo()); } if (shouldCheckExistence && hasExistingEntities(entityToAdd)) { String error = String.format(ERROR_CREATE_ENTITY_ALREADY_EXISTS, entityToAdd.toString()); throw new EntityAlreadyExistsException(error); } E entity = convertToEntityForSaving(entityToAdd); ofy().save().entity(entity).now(); log.info("Entity created: " + JsonUtils.toJson(entityToAdd)); return makeAttributes(entity); } E convertToEntityForSaving(A entityAttributes) throws EntityAlreadyExistsException { return entityAttributes.toEntity(); } /** * Checks whether there are existing entities in the database. */ abstract boolean hasExistingEntities(A entityToCreate); /** * Puts an entity in the database without existence checking. * * <p>The document of the associated entity (if applicable) WILL NOT be updated. * * @return created entity * @throws InvalidParametersException if entity to put is not valid */ public A putEntity(A entityToAdd) throws InvalidParametersException { try { return createEntity(entityToAdd, false); } catch (EntityAlreadyExistsException e) { assert false : "Unreachable branch"; return null; } } /** * Puts a collection of entity in the database without existence checking. * * <p>The documents of the associated entities (if applicable) WILL NOT be updated. * * @return created entities * @throws InvalidParametersException if any of entity to add is not valid */ public List<A
Assistant: