I have watched Congressman Keating since his election. He is an strong and dedicated to constituents. I am a Realtor who believes in protecting property rights of homeowners. Congressman Keating understands the housing issues such as Flood insurance, protecting the Mortgage Interest Tax Deduction and other such issues.
Judging for the closed-ness of Apple, you probably won't get much credible answer from Apple's own people. OS X and iOS are primarily written in Objective-C with some C++ in between (e.g. IOKit, WebKit, etc) and probably some C as well for the kernel stuff. However looking at Apple's software engineering jobs vacancies [1], these are also relevant programming languages at Apple: Java.
That line of code is written in the Python programming language. Put simply, a programming (or coding) language is a set of syntax rules that define how code should be written and formatted. Thousands of different programming languages make it possible for us to create computer software, apps and websites.