Add llms subdir + update README (#145)

* add llms subdir + update README

* nits

* use same pre-commit as mlx

* update readmes a bit

* format

llms/phi2/convert.py

@@ -0,0 +1,24 @@
+import numpy as np
+from transformers import AutoModelForCausalLM
+
+
+def replace_key(key: str) -> str:
+    if "wte.weight" in key:
+        key = "wte.weight"
+
+    if ".mlp" in key:
+        key = key.replace(".mlp", "")
+    return key
+
+
+def convert():
+    model = AutoModelForCausalLM.from_pretrained(
+        "microsoft/phi-2", torch_dtype="auto", trust_remote_code=True
+    )
+    state_dict = model.state_dict()
+    weights = {replace_key(k): v.numpy() for k, v in state_dict.items()}
+    np.savez("weights.npz", **weights)
+
+
+if __name__ == "__main__":
+    convert()