///

### Step 2: create a `FastAPI` "instance" { #step-2-create-a-fastapi-instance }

{* ../../docs_src/first_steps/tutorial001_py39.py hl[3] *}

Here the `app` variable will be an "instance" of the class `FastAPI`.

This will be the main point of interaction to create all your API.

### Step 3: create a *path operation* { #step-3-create-a-path-operation }

#### Path { #path }

///

### Schritt 2: Erzeugen einer `FastAPI`-„Instanz“ { #step-2-create-a-fastapi-instance }

{* ../../docs_src/first_steps/tutorial001_py39.py hl[3] *}

In diesem Beispiel ist die Variable `app` eine „Instanz“ der Klasse `FastAPI`.

Dies wird der Hauptinteraktionspunkt für die Erstellung all Ihrer APIs sein.

### Schritt 3: Erstellen einer *Pfadoperation* { #step-3-create-a-path-operation }

        if (StringUtil.isBlank(projectId)) {
            throw new CrawlingAccessException(
                    "GCS project ID is blank. Please set the GCS_PROJECT_ID environment variable or projectId parameter.");
        }

        final StorageOptions.Builder builder = StorageOptions.newBuilder().setProjectId(projectId);

//
// If any file inside the archive uses a non-local name
// (as defined by [filepath.IsLocal]) or a name containing backslashes
// and the GODEBUG environment variable contains `zipinsecurepath=0`,
// OpenReader returns the reader with an ErrInsecurePath error.
// A future version of Go may introduce this behavior by default.
// Programs that want to accept non-local names can ignore

Imagine that you want the parameter to be `item-query`.

Like in:

```
http://127.0.0.1:8000/items/?item-query=foobaritems
```

But `item-query` is not a valid Python variable name.

The closest would be `item_query`.

But you still need it to be exactly `item-query`...

Then you can declare an `alias`, and that alias is what will be used to find the parameter value:

	for metricName, mv := range m.values {
		desc := m.descriptors[metricName]
		promDesc := desc.toPromDesc(namePrefix, extraLabels)
		for _, v := range mv {
			// labelValues is in the same order as the variable labels in the
			// descriptor.
			labelValues := make([]string, 0, len(v.Labels))
			for _, k := range desc.VariableLabels {
				labelValues = append(labelValues, v.Labels[k])
			}
			metrics = append(metrics,

#{divide($fs-min, $rfs-rem-value)}rem, #{$fs-min}px);\n\n      // Use `vmin` if two-dimensional is enabled\n      $variable-unit: if($rfs-two-dimensional, vmin, vw);\n\n      // Calculate the variable width between 0 and $rfs-breakpoint\n      $variable-width: #{divide($fs-diff * 100, $rfs-breakpoint)}#{$variable-unit};\n\n      // Set the calculated font-size\n      $rfs-fluid: calc(#{$min-width} + #{$variable-width}) #{$rfs-suffix};\n\n      // Breakpoint formatting\n      $mq-value: if($rfs-breakpoint-unit ==...

///

### Paso 2: crea una "instance" de `FastAPI` { #step-2-create-a-fastapi-instance }

{* ../../docs_src/first_steps/tutorial001_py39.py hl[3] *}

Aquí la variable `app` será una "instance" de la clase `FastAPI`.

Este será el punto principal de interacción para crear toda tu API.

### Paso 3: crea una *path operation* { #step-3-create-a-path-operation }

#### Path { #path }

	newConfig, err := loadTierConfig(ctx, objAPI)

	config.Lock()
	defer config.Unlock()

	switch err {
	case nil:
		break
	case errConfigNotFound: // nothing to reload
		// To maintain the invariance that lastRefreshedAt records the
		// timestamp of last successful refresh
		config.lastRefreshedAt = UTCNow()
		return nil
	default:
		return err
	}

	// Reset drivercache built using current config

/// info | 정보

이미 가상 환경에 대해 잘 알고 있다면, 이 섹션은 건너 뛰어도 괜찮습니다. 🤓

///

/// tip | 팁

**가상 환경(Virtual Environment)** 은 **환경 변수(Environment Variable)** 와 다릅니다.

**환경 변수**는 시스템에 존재하며, 프로그램이 사용할 수 있는 변수입니다.

**가상 환경**은 몇몇 파일로 구성된 하나의 디렉터리입니다.

///

/// info | 정보

이 페이지에서는 **가상 환경**의 사용 방법과 작동 방식을 설명합니다.