I prefer if the author pointed out to course in edx on Data Science and Machine learning. 
Python is slowly becoming the gold standard for Machine and Deep Learning. Since Python has been very strong in scientific and artificial intelligence community there is a large corpus of knowledge.
Given how easy it is to go from experiment to a live web service using python you don&#x27;t need to fiddle with hundreds of xml configuration and infrastructure to just get it to work. Also with Anaconda and jupyter you can share your knowledge so easy.
Julia is catching up which is good, but its still very far from Python.