end

    rect rgba(0, 255, 0, .1)
        code ->> function: say_hi(name="Rick")
        function ->> execute: execute function code
        execute ->> code: return the result
    end

    rect rgba(0, 255, 0, .1)
        code ->> function: say_hi(name="Rick", salutation="Mr.")
        function ->> execute: execute function code
        execute ->> code: return the result
    end

```Dockerfile
CMD ["fastapi", "run", "app/main.py", "--proxy-headers", "--port", "80"]
```

#### Docker Cache

There's an important trick in this `Dockerfile`, we first copy the **file with the dependencies alone**, not the rest of the code. Let me tell you why is that.

```Dockerfile
COPY ./requirements.txt /code/requirements.txt
```