As discussed in #3926, the following files do not have `.py` extensions because [TensorFlow does not yet support the current Python](https://github.com/tensorflow/tensorflow/issues/44485). * dynamic_programming/k_means_clustering_tensorflow.py_tf * machine_learning/lstm/lstm_prediction.py_tf * neural_network/gan.py_tf * neural_network/input_data.py_tf TODO: Restore the `.py` file extensions and ensure our tests pass when TensorFlow supports the current Python.