Keras is a leading open-source Python library written for constructing neural networks and machine learning projects. It can run on Deeplearning4j, MXNet, Microsoft Cognitive Toolkit (CNTK), Theano or TensorFlow. It offers almost all standalone modules including optimizers, neural layers, activation functions, initialization schemes, cost functions, and regularization schemes. It makes it easy to add new modules just like adding new functions and classes. As the model is already defined in the code, you don’t need to have a separate model config files.