{* ../../docs_src/events/tutorial003_py310.py hl[1,13] *}

A **context manager** in Python is something that you can use in a `with` statement, for example, `open()` can be used as a context manager:

```Python
with open("file.txt") as file:
    file.read()
```

In recent versions of Python, there's also an **async context manager**. You would use it with `async with`:

```Python

        this.serviceName = serviceName;
    }

    /**
     * Create an authenticator using the given credentials
     *
     * This will create a JAAS configuration that is used to obtain a TGT.
     *
     * @param domain the domain for authentication
     * @param username the username for authentication
     * @param password the password for authentication
     */

	defer ticker.Stop()
	for _, obs := range observations {
		// Send observations once every 1ms, to simulate delay between
		// observations. This is to test the channel based
		// synchronization used internally.
		<-ticker.C
		ttfbHist.With(prometheus.Labels{"api": obs.label}).Observe(obs.val)
	}

	metrics := getHistogramMetrics(ttfbHist, getBucketTTFBDistributionMD(), false, false)

	// When FileNameFunc is not specified, DefaultFilenameFunc will be used.
	FileNameFunc func() string

	// Compress specify if you want the logs to be compressed after rotation.
	Compress bool
}

// Writer is a concurrency-safe writer with file rotation.
type Writer struct {
	// opts are the configuration options for this Writer
	opts Options

	// f is the currently open file used for appends.

<module>
<source path="">
  <!-- Hack to keep collect from hiding collect.testing supersource: -->
  <exclude name="**/testing/**"/>
</source>

<!--
    We used to set this only for packages that had manual supersource. That
    worked everywhere that I know of except for one place: when running the GWT
    util.concurrent tests under Guava.

    The problem is that GWT responds poorly to two .gwt.xml files in the same
    Java package; see

     * @param request The model building request that holds further settings, must not be {@code null}.
     * @param problems The container used to collect problems that were encountered, must not be {@code null}.
     */
    void expandPluginConfiguration(Model model, ModelBuildingRequest request, ModelProblemCollector problems);

        }

        return filePath;
    }

    /**
     * Returns the character set used for content encoding.
     * @return the charset
     */
    public String getCharset() {
        return charset;
    }

    /**
     * Sets the character set used for content encoding.
     * @param charset the charset to set
     */
    public void setCharset(final String charset) {

import org.lastaflute.web.validation.Required;

/**
 * Form for uploading stopwords files to the Fess search engine.
 * Stopwords are common words that should be ignored during search indexing and querying.
 * This form is used in the admin interface to upload custom stopwords dictionary files.
 */
public class UploadForm {

    /**
     * The dictionary ID that identifies which stopwords dictionary configuration to update.

     * Add a rule which will skip SHA checking for the given dependency name. This should be used for
     * locally build dependencies, which cause the sha to change constantly.
     */
    public void ignoreSha(String dep) {
        ignoreShas.add(dep);
    }

    /**
     * Add a file that should be ignored by the check. This should be used for additional license files not tied to jar dependency
     */

   * contains any match for the given regular expression pattern. The test used is equivalent to
   * {@code Pattern.compile(pattern).matcher(arg).find()}
   *
   * @throws IllegalArgumentException if the pattern is invalid
   * @since 3.0
   */
  @GwtIncompatible // Only used by other GWT-incompatible code.
  public static Predicate<CharSequence> containsPattern(String pattern) {