chore: import upstream snapshot with attribution

functions/function_calling/user.py

@@ -0,0 +1,17 @@
+def call_user(instruction: str, _context: dict | None = None) -> str:
+    """
+    If you think it's necessary to get input from the user, use this function to send the instruction to the user and get their response.
+
+    Args:
+        instruction: The instruction to send to the user.
+    """
+    prompt = _context.get("human_prompt") if _context else None
+    if prompt is None:
+        return f"Human prompt unavailable, default response for instruction: {instruction}"
+    result = prompt.request(
+        node_id=_context.get("node_id", "model_function_calling"),
+        task_description="Please response to the model instruction.",
+        inputs=instruction,
+        metadata={"source": "function_tool"},
+    )
+    return result.text