This python project allows a mac computer to randomly generate phonetic compositions, which can be read (or "sung") by the built-in macOS North American English speech synthesizer.

(Presuming you have python installed) run the python program sing; I use terminal with the following commands:
$ cd [path to python project]
$ python sing.py --live
The --live argument causes your mac to immediately sing the resultant file.
Optional: Manually tell your mac to read the output file. This can be done in terminal with:
$ python sing.py
and $ say -f out.txt or by opening out.txt, right clicking, and selecting speech>start speaking.

A programming guide for the macOS speech synthesis API can be found here: http://mirror.informatimago.com/next/developer.apple.com/documentation/UserExperience/Conceptual/SpeechSynthesisProgrammingGuide/SpeechSynthesisProgrammingGuide.pdf
Install Python here:
https://www.python.org/downloads/mac-osx/