text: from typing import List, Optional
  
  from fastapi import FastAPI
  from pydantic import BaseModel
  
  app = FastAPI()
  
  
  class Item(BaseModel):
      name: str
      description: Optional[str] = None
      price: float
      tax: Optional[float] = None
      tags: List[str] = []
  
  
  @app.post("/items/", response_model=Item)
  async def create_item(item: Item):
      return item
  