from pydantic import BaseModel

class User(BaseModel):
    id: int
    name: str
    email: str

async def get_user_from_db(user_id: int) -> User:
    # Simulate database access
    return User(id=user_id, name="John Doe", email="johndoe@example.com")

@app.get("/user/{user_id}")
async def get_user(user_id: int) -> User:
    cache_key = f"user_{user_id}"
    cached_user = await get_cache(cache_key)
    if cached_user:
        return User.parse_raw(cached_user)
    
    user = await get_user_from_db(user_id)
    await set_cache(cache_key, user.json())
    return user