Text generation with GPT-2 in Ruby

Many people think that accessing AI from languages other than Python is too difficult. Recently, however, a large number of pre-trained models have been published, making it easy to run AI inference from a variety of platforms and programming languages. Here, I would like to run the ONNX runtime and try out the GPT-2 model that generates English sentences from the Ruby language. Inference is easy with ONNX Runtime.