```python
from fastapi import FastAPI, HTTPException
import helpers

app = FastAPI()


@app.post("/orders", status_code=201)
async def create_order(payload: dict):
    item = payload.get("item")
    if item is None:
        raise HTTPException(status_code=400, detail="item required")
    audit_line = f"order:{item}"
    await helpers.aappend_audit_line(audit_line)
    return {"status": "created"}
```