Textbooks Are All You Need II: phi-1.5 technical report 2023 article li2023phi15 Authors Yuanzhi Li, Sebastien Bubeck, Ronen Eldan, Allie Del Giorno, Suriya Gunasekar, Yin Tat Lee Venue arXiv preprint arXiv:2309.05463 URL https://arxiv.org/abs/2309.05463