Add a python client library

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client-libs/python/openpipe/merge_openai_chunks.py

@@ -0,0 +1,42 @@
+from typing import Any, Optional
+
+
+def merge_streamed_chunks(base: Optional[Any], chunk: Any) -> Any:
+    if base is None:
+        return merge_streamed_chunks({**chunk, "choices": []}, chunk)
+
+    choices = base["choices"].copy()
+    for choice in chunk["choices"]:
+        base_choice = next((c for c in choices if c["index"] == choice["index"]), None)
+
+        if base_choice:
+            base_choice["finish_reason"] = (
+                choice.get("finish_reason") or base_choice["finish_reason"]
+            )
+            base_choice["message"] = base_choice.get("message") or {"role": "assistant"}
+
+            if choice.get("delta") and choice["delta"].get("content"):
+                base_choice["message"]["content"] = (
+                    base_choice["message"].get("content") or ""
+                ) + (choice["delta"].get("content") or "")
+            if choice.get("delta") and choice["delta"].get("function_call"):
+                fn_call = base_choice["message"].get("function_call") or {}
+                fn_call["name"] = (fn_call.get("name") or "") + (
+                    choice["delta"]["function_call"].get("name") or ""
+                )
+                fn_call["arguments"] = (fn_call.get("arguments") or "") + (
+                    choice["delta"]["function_call"].get("arguments") or ""
+                )
+        else:
+            # Here, we'll have to handle the omitted property "delta" manually
+            new_choice = {k: v for k, v in choice.items() if k != "delta"}
+            choices.append(
+                {**new_choice, "message": {"role": "assistant", **choice["delta"]}}
+            )
+
+    merged = {
+        **base,
+        "choices": choices,
+    }
+
+    return merged