Creating the first endpoint and running it locally

FastAPI is a framework that aims at being easy to use and quick to write. In the following example, you'll realize that this is not just a promise. In fact, creating an API endpoint involves just a few lines:

chapter3_first_endpoint_01.py

from fastapi import FastAPI
app = FastAPI()
@app.get("/")
async def hello_world():
    return {"hello": "world"}

https://github.com/PacktPublishing/Building-Data-Science-Applications-with-FastAPI/blob/main/chapter3/chapter3_first_endpoint_01.py

In this example, we define a GET endpoint at the root path, which always returns the {"hello": "world"} JSON response. To do this, we first instantiate a FastAPI object, app. This will be the main application object that will wire all of the API routes.

Then, we simply define a coroutine that contains our route logic, the path operation function. Its return value is automatically...