例如，<a href="https://docs.python.org/zh-cn/3/tutorial/inputoutput.html#reading-and-writing-files" class="external-link" target="_blank">你可以使用`with`读取文件</a>：

```Python
with open("./somefile.txt") as f:
    contents = f.read()
    print(contents)
```

在底层，`open("./somefile.txt")`创建了一个被称为"上下文管理器"的对象。

当 `with` 代码块结束时，它会确保关闭文件，即使发生了异常也是如此。

当你使用 `yield` 创建一个依赖项时，**FastAPI** 会在内部将其转换为上下文管理器，并与其他相关工具结合使用。

{* ../../docs_src/query_params_str_validations/tutorial013_an_py39.py hl[9] *}

/// note

Keep in mind that in this case, FastAPI won't check the contents of the list.

For example, `list[int]` would check (and document) that the contents of the list are integers. But `list` alone wouldn't.

///

## Declare more metadata { #declare-more-metadata }

You can add more information about the parameter.

import jcifs.CIFSException;
import jcifs.Config;
import jcifs.config.PropertyConfiguration;
import jcifs.context.BaseContext;
import jcifs.netbios.UniAddress;
import jcifs.smb.NtlmPasswordAuthentication;
import jcifs.smb.SmbAuthException;

/**
 * This servlet may be used with pre-2.3 servlet containers
 * to protect content with NTLM HTTP Authentication. Servlets that
 * extend this abstract base class may be authenticated against an SMB

	if objAPI == nil {
		writeErrorResponse(ctx, w, errorCodes.ToAPIErr(ErrServerNotInitialized), r.URL)
		return
	}

	vars := mux.Vars(r)
	bucket := vars["bucket"]

	// PutBucketLifecycle always needs a Content-Md5
	if !validateLengthAndChecksum(r) {
		writeErrorResponse(ctx, w, errorCodes.ToAPIErr(ErrMissingContentMD5), r.URL)
		return
	}

	if !yes {
		return errNotConnected
	}

	return nil
}

// NewWebhookTarget - creates new Webhook target.
func NewWebhookTarget(ctx context.Context, id string, args WebhookArgs, loggerOnce logger.LogOnce, transport *http.Transport) (*WebhookTarget, error) {
	ctx, cancel := context.WithCancel(ctx)

	target := &WebhookTarget{
		id:         event.TargetID{ID: id, Name: "webhook"},
		args:       args,
		loggerOnce: loggerOnce,

## Scope

This Code of Conduct applies to all content on tensorflow.org, TensorFlow’s GitHub organization, or any other official TensorFlow web presence allowing for community interactions, as well as at all official TensorFlow events, whether offline or online.

    if (entries.size() >= 1) {
      a = entries.get(0);
      if (entries.size() >= 3) {
        b = entries.get(1);
        c = entries.get(2);
      }
    }
  }

  /** Resets the contents of navigableMap to have entries a, c, for the navigation tests. */
  @SuppressWarnings("unchecked") // Needed to stop Eclipse whining
  private void resetWithHole() {

    if (values.size() >= 1) {
      a = values.get(0);
      if (values.size() >= 3) {
        b = values.get(1);
        c = values.get(2);
      }
    }
  }

  /** Resets the contents of navigableSet to have elements a, c, for the navigation tests. */
  protected void resetWithHole() {
    super.resetContainer(getSubjectGenerator().create(a, c));
    navigableSet = (NavigableSet<E>) getSet();
  }

 */
@GwtCompatible
public final class MinMaxPriorityQueue<E> extends AbstractQueue<E> {

  /**
   * Creates a new min-max priority queue with default settings: natural order, no maximum size, no
   * initial contents, and an initial expected size of 11.
   */
  public static <E extends Comparable<E>> MinMaxPriorityQueue<E> create() {
    return new Builder<Comparable<E>>(Ordering.natural()).create();
  }

  /**

     */
    @Required
    public String scriptType;

    /**
     * The script data or code that was executed.
     * This field contains the actual script content that was run.
     */
    public String scriptData;

    /**
     * The result or output from the script execution.
     * This field contains any output or result data from the script.
     */