* `^`: Inicia com os seguintes caracteres, ou seja, não contém caracteres anteriores.
* `fixedquery`: contém o valor exato `fixedquery`.
* `$`: termina aqui, não contém nenhum caractere após `fixedquery`.

Se você se sente perdido com todo esse assunto de **"expressão regular"**, não se preocupe. Esse é um assunto complicado para a maioria das pessoas. Você ainda pode fazer muitas coisas sem utilizar expressões regulares.

```Python hl_lines="14"
{!> ../../docs_src/body_nested_models/tutorial002.py!}
```

////

## Set types

But then we think about it, and realize that tags shouldn't repeat, they would probably be unique strings.

And Python has a special data type for sets of unique items, the `set`.

Then we can declare `tags` as a set of strings:

//// tab | Python 3.10+

```Python hl_lines="12"

	return ipList
}

func mustGetLocalLoopbacks() (ipList set.StringSet) {
	ipList = set.NewStringSet()
	for _, ip := range mustGetLocalIPs() {
		if ip != nil && ip.IsLoopback() {
			ipList.Add(ip.String())
		}
	}
	return
}

// mustGetLocalIP4 returns IPv4 addresses of localhost.  It panics on error.
func mustGetLocalIP4() (ipList set.StringSet) {
	ipList = set.NewStringSet()
	for _, ip := range mustGetLocalIPs() {

			// When the client disconnects before getting the S3 handler
			// status code response, set the status code to 499 so this request
			// will be properly audited and traced.
			w.WriteHeader(499)
		default:
			globalHTTPStats.addRequestsInQueue(-1)
			if contextCanceled(ctx) {
				w.WriteHeader(499)
				return
			}
			// Send a http timeout message
			writeErrorResponse(ctx, w,

	if objInfo.ModTime.IsZero() || objInfo.ModTime.Equal(time.Unix(0, 0)) {
		return false
	}

	// Headers to be set of object content is not going to be written to the client.
	writeHeaders := func() {
		// set common headers
		setCommonHeaders(w)

		// set object-related metadata headers
		w.Header().Set(xhttp.LastModified, objInfo.ModTime.UTC().Format(http.TimeFormat))

		if objInfo.ETag != "" {

		defer cancel()

		if prefix == "" {
			// if all objects are not deleted yet this call may fail.
			return clnt.RemoveBucket(cctx, bucket)
		}

		objectsCh := make(chan minio.ObjectInfo)

		// Send object names that are needed to be removed to objectsCh
		go func() {
			defer xioutil.SafeClose(objectsCh)
			opts := minio.ListObjectsOptions{
				Prefix:    prefix,
				Recursive: true,
			}

The benefit of raising an exception over `return`ing a value will be more evident in the section about Dependencies and Security.

		}

		var prevResIps []*cniv1.IPConfig
		if conf.PrevResult != nil {
			prevResult := conf.PrevResult.(*cniv1.Result)
			prevResIps = prevResult.IPs
		}

		// Only send event if this pod "would be" an ambient-watched pod - otherwise skip
		if podIsAmbient {
			cniEventAddr := filepath.Join(conf.CNIAgentRunDir, constants.CNIEventSocketName)

 *  Fix: Improve connection timeout recovery.
 *  Fix: Recover from `getsockname` crashes impacting Android releases prior to
    4.2.2.
 *  Fix: Drop partial support for HTTP/1.0. Previously OkHttp would send
    `HTTP/1.0` on connections after seeing a response with `HTTP/1.0`. The fixed
    behavior is consistent with Firefox and Chrome.
 *  Fix: Allow a body in `OPTIONS` requests.

// NewReader then it should be set to -1.
// When size is >=0 it *must* match the amount of data provided by r.
//
// NewReader may try merge the given size, MD5 and SHA256 values
// into src - if src is a Reader - to avoid computing the same
// checksums multiple times.
// NewReader enforces S3 compatibility strictly by ensuring caller
// does not send more content than specified size.