```python
import asyncio
from fastapi import FastAPI, Body

import helpers  # noqa: F401  (the provided API)

app = FastAPI()


@app.post("/documents", status_code=201)
async def save_document_endpoint(name: str = Body(...), text: str = Body(...)):
    loop = asyncio.get_event_loop()
    bytes_count = await loop.run_in_executor(None, helpers.save_document, name, text)
    return {"bytes": bytes_count}
```