transformers pytorch gpt_bigcode text-generation Code-Gen dataset:bigcode/the-stack-dedup dataset:teknium1/GPTeacher-codegen arxiv:1911.02150 arxiv:2205.14135 arxiv:2207.14255 arxiv:2305.06161 license:bigcode-openrail-m autotrain_compatible text-generation-inference endpoints_compatible region:us