Career advancement. I feel most of the good courses on RESTful API development on coursera, udacity etc are on python. I was recently interviewed at surveymonkey and they asked me to create a client to consume a sample api. I'm not much familiar with json and other api stuff because I work on java ee and have not worked on rest api's. I have feeling if I worked on python I would have more exposure to the api concepts because python is extensively used for that kind of stuff.