Blame for config.json

```json
{
  "model_type": "gpt2",
  "architectures": ["GPT2LMHeadModel"],
  "n_embd": 256,
  "n_layer": 4,
  "n_head": 4,
  "n_positions": 256,
  "n_ctx": 256,
  "vocab_size": 50257
}