Description

This is a very minor question on chosen syntax. Why not use the return type annotation for the response_model? For example rather than:

@app.post("/items/", response_model=Item)
async def create_item(*, item: Item):
    return item

You could concievably go:

@app.post("/items/") 
async def create_item(*, item: Item) -> Item:
    return item

which just seems like it uses the language facilities better and is a bit more pythonic. There is no real change in feature set, and I am sure i was thought of, but what was the reasoning behind not doing it?