A TensorFlow writer is used to write processed data to TFRecord files in the data preparation. To create a new writer you should inherit from the general TFWriter class defined in tfwriter.py and overwrite the abstract methods. You should then add it to the factory method in tfwriter_factory.py. It is also very helpful to create a default configuration in the defaults directory. The name of the file should be the name of the class in lower case with the .cfg extension.