Most AI frameworks support Python out of the box, including TensorFlow, PyTorch, Theano, and CAFFE/CAFFE2, which together currently have the most developer mindshare. Every single TensorFlow, Pytorch, Theano, and CAFFE/CAFFE2 tutorial or example is written in Python.
With very few exceptions (e.g., the occasional Lua code coming out of Yann Le Cun's group at FB), new AI papers come with code written in Python.
If you want to see Python's utter dominance in this field, just search for "deep learning" or "neural net" on github.