TFMOT 0.4.0 is the last release to support Python 2. Python 2 support [officially ended on January 1, 2020](https://www.python.org/dev/peps/pep-0373/#update) and [TF 2.1.0](https://github.com/tensorflow/tensorflow/releases/tag/v2.1.0) was the last release to support Python 2.
Keras clustering API:
* New API for weight clustering
* Major Features
* Support for clustering convolutional (except DepthwiseConv), Dense and other commonly used standard Keras layers
* Support for different initialization methods for the cluster centroids: density-based, linear, random
* Fine-tuning of cluster centroids during training
* Tested against TensorFlow 1.14.0, 2.0.0, and nightly, and Python 3.
Keras quantization API:
* Bug Fixes and Other Changes
* Fixed Sequential model support for BatchNorm layers that follow Conv/DepthwiseConv ([issue](https://github.com/tensorflow/model-optimization/issues/378)).
* Improved error message for not using `quantize_scope` with custom Keras layers and objects.
* Tested against TensorFlow nightly, and Python 2/3.
Keras pruning API:
* Tested against TensorFlow 1.14.0, 2.0.0, and nightly, and Python2/3.