code: public Entity get(String keyName) {
      Datastore datastore = transaction.getDatastore();
      // [START get]
      Key key = datastore.newKeyFactory().setKind("MyKind").newKey(keyName);
      Entity entity = transaction.get(key);
      transaction.commit();
      // Do something with the entity
      // [END get]
      return entity;
    }
docs: [VARIABLE "my_key_name"]