You could also use it to generate code automatically, for clients that communicate with your API. For example, frontend, mobile or IoT applications.

## Recap, step by step

### Step 1: import `FastAPI`

```Python hl_lines="1"
{!../../../docs_src/first_steps/tutorial001.py!}
```

`FastAPI` is a Python class that provides all the functionality for your API.

!!! note "Technical Details"

## Previous Steps Before Starting

There are many cases where you want to perform some steps **before starting** your application.

For example, you might want to run **database migrations**.

But in most cases, you will want to perform these steps only **once**.

So, you will want to have a **single process** to perform those **previous steps**, before starting the application.

    The `--upgrade` option tells `pip` to upgrade the packages if they are already installed.

    Because the previous step copying the file could be detected by the **Docker cache**, this step will also **use the Docker cache** when available.

This is normally called a **webhook**.

## Webhooks steps

The process normally is that **you define** in your code what is the message that you will send, the **body of the request**.

You also define in some way at which **moments** your app will send those requests or events.

         - current: ...
         - baseline: ...
     
     See failure report at file:///<path to Gradle checkout>/subprojects/architecture-test/build/reports/binary-compatibility/report.html
```

Here are the steps to resolve the issue:

1. Open the failure report mentioned in the output.\
If you don't see the report link in the output in the IDE, make sure to select the top-level node in the structured output panel.

* Security - HTTPS
* Running on startup
* Restarts
* Replication (the number of processes running)
* Memory
* Previous steps before starting

* Add translation to Chinese for [First Steps - 第一步](https://fastapi.tiangolo.com/zh/tutorial/first-steps/). PR [#1323](https://github.com/tiangolo/fastapi/pull/1323) by [@waynerv](https://github.com/waynerv).

# Tutorial - User Guide

This tutorial shows you how to use **FastAPI** with most of its features, step by step.

Each section gradually builds on the previous ones, but it's structured to separate topics, so that you can go directly to any specific one to solve your specific API needs.

It is also built to work as a future reference.

So you can come back and see exactly what you need.

## Run the code