Keras adversarial (https://github.com/bstriner/keras-adversarial) is an open source Python package for building GANs developed by Ben Striner (https://github.com/bstriner and https://github.com/bstriner/keras-adversarial/blob/master/LICENSE.txt). Since Keras just recently moved to 2.0, I suggest downloading latest Keras adversarial package:
git clone --depth=50 --branch=master https://github.com/bstriner/keras-adversarial.git
And install setup.py:
python setup.py install
Note that compatibility with Keras 2.0 is tracked in this issue https://github.com/bstriner/keras-adversarial/issues/11.
 If the generator G and the discriminator D are based on the same model, M, then they can be combined into an adversarial model; it uses the same input, M, but separates targets and metrics for G and D. The library has the following API call:
adversarial_model...
