### Criando o Código do **FastAPI**

* Crie um diretório `app` e entre nele.
* Crie um arquivo vazio `__init__.py`.
* Crie um arquivo `main.py` com:

```Python
from typing import Optional

from fastapi import FastAPI

app = FastAPI()


@app.get("/")
def read_root():
    return {"Hello": "World"}


@app.get("/items/{item_id}")

!!! tip "Tipp"
    Um alle Konfigurationen und Optionen anzuzeigen, gehen Sie zur Docker-Image-Seite: <a href="https://github.com/tiangolo/uvicorn-gunicorn-fastapi-docker" class="external-link" target="_blank">tiangolo/uvicorn-gunicorn-fastapi</a>.

    The `--no-cache-dir` option tells `pip` to not save the downloaded packages locally, as that is only if `pip` was going to be run again to install the same packages, but that's not the case when working with containers.

    !!! note
        The `--no-cache-dir` is only related to `pip`, it has nothing to do with Docker or containers.