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 { #recap-step-by-step }

### Step 1: import `FastAPI` { #step-1-import-fastapi }

{* ../../docs_src/first_steps/tutorial001.py hl[1] *}

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

        assertFalse(cacheEntry.isComplete());

        // Step 3: Verify can cache directory listing
        assertTrue(directoryLeaseManager.canCacheDirectoryListing(directoryPath));

        // Step 4: Initially no cached listing
        assertNull(directoryLeaseManager.getCachedDirectoryListing(directoryPath));

        // Step 5: Simulate directory enumeration and update cache

## ステップ毎の要約

### Step 1: `FastAPI`をインポート

{* ../../docs_src/first_steps/tutorial001.py hl[1] *}

`FastAPI`は、APIのすべての機能を提供するPythonクラスです。

/// note | 技術詳細

`FastAPI`は`Starlette`を直接継承するクラスです。

`FastAPI`でも<a href="https://www.starlette.io/" class="external-link" target="_blank">Starlette</a>のすべての機能を利用可能です。

///

### Step 2: `FastAPI`の「インスタンス」を生成

    ///

    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.

It is easy to assume that HTTPS is something that is just "enabled" or not.

But it is way more complex than that.

/// tip

If you are in a hurry or don't care, continue with the next sections for step by step instructions to set everything up with different techniques.

///

          "instant": true,
          "interval": "",
          "intervalFactor": 1,
          "legendFormat": "",
          "metric": "process_start_time_seconds",
          "refId": "A",
          "step": 60
        }
      ],
      "title": "Total Drives",
      "type": "stat"
    },
    {
      "datasource": {
        "type": "prometheus",
        "uid": "${DS_PROMETHEUS}"
      },

    init: GradleBuildStep.() -> Unit,
    custom: GradleBuildStep.() -> Unit,
): GradleBuildStep =
    GradleBuildStep(init)
        .apply(custom)
        .also {
            step(it)
        }

/**
 * Adds a [Gradle build step](https://confluence.jetbrains.com/display/TCDL/Gradle)
 * that runs with the Gradle wrapper.
 *
 * @see GradleBuildStep
 */
fun BuildSteps.gradleWrapper(
    buildType: BuildType? = null,

{* ../../docs_src/security/tutorial005_an_py310.py hl[5,9,13,47,65,106,108:116,122:126,130:136,141,157] *}

Now let's review those changes step by step.

## OAuth2 Security scheme { #oauth2-security-scheme }

The first change is that now we are declaring the OAuth2 security scheme with two available scopes, `me` and `items`.

We’ve included deprecated APIs in OkHttp 4.0 because they make migration easy. We will remove them
in a future release! If you’re skipping releases, it’ll be much easier if you upgrade to OkHttp 4.0
as an intermediate step.

#### Vars and Vals

Java doesn’t have language support for properties so developers make do with getters and setters.
Kotlin does have properties and we take advantage of them in OkHttp.

    k1 = mixK1(high);
    h1 = mixH1(h1, k1);

    return fmix(h1, Longs.BYTES);
  }

  @Override
  public HashCode hashUnencodedChars(CharSequence input) {
    int h1 = seed;

    // step through the CharSequence 2 chars at a time
    for (int i = 1; i < input.length(); i += 2) {
      int k1 = input.charAt(i - 1) | (input.charAt(i) << 16);
      k1 = mixK1(k1);
      h1 = mixH1(h1, k1);
    }