```python
from fastapi import FastAPI

import helpers

app = FastAPI()


@app.get("/portfolio")
async def get_portfolio(symbols: str):
    symbols_list = symbols.split(",")
    tasks = [helpers.afetch_price(symbol) for symbol in symbols_list]
    prices = await asyncio.gather(*tasks)
    return {"prices": dict(zip(symbols_list, prices))}
```