{* ../../docs_src/sql_databases/tutorial001_an_py310.py ln[21:22] hl[21:22] *}

### Create a Session Dependency { #create-a-session-dependency }

A **`Session`** is what stores the **objects in memory** and keeps track of any changes needed in the data, then it **uses the `engine`** to communicate with the database.

// When adding/removing fields, regenerate the marshal code using the go generate above.
// Only changing meaning of fields requires a version bump.
// bucketMetadataFormat refers to the format.
// bucketMetadataVersion can be used to track a rolling upgrade of a field.
type BucketMetadata struct {
	Name                        string
	Created                     time.Time
	LockEnabled                 bool // legacy not used anymore.

    reuse pod names (they use generate-name).
  * User-written controllers that reuse names of pod objects should evaluate this change.
  * When deleting an object with `kubectl delete ... --grace-period=0`, the client will
    begin a graceful deletion and wait until the resource is fully deleted.  To force
    deletion immediately, use the `--force` flag. This prevents users from accidentally

gradient-bg($custom-range-thumb-active-bg);\n    }\n  }\n\n  &::-webkit-slider-runnable-track {\n    width: $custom-range-track-width;\n    height: $custom-range-track-height;\n    color: transparent; // Why?\n    cursor: $custom-range-track-cursor;\n    background-color: $custom-range-track-bg;\n    border-color: transparent;\n    @include border-radius($custom-range-track-border-radius);\n    @include box-shadow($custom-range-track-box-shadow);\n  }\n\n  &::-moz-range-thumb {\n    width: $custom-range-thumb-width;\n...

				return
			}
		}
	}()
	return func(err error) {
		if doneCh == nil {
			return
		}

		// Indicate we are ready to write.
		doneCh <- err

		// Wait for channel to be closed so we don't race on writes.
		<-doneCh

		// Clear so we can be called multiple times without crashing.
		doneCh = nil
	}, &closeNotifier{rc: r.Body, done: bodyDoneCh}
}

            transformHeader.encode(result, 0);
            System.arraycopy(encResult.ciphertext, 0, result, Smb2TransformHeader.TRANSFORM_HEADER_SIZE, encResult.ciphertext.length);

            // Track encrypted bytes for key rotation - lock-free atomic operation
            bytesEncrypted.addAndGet(message.length);

            return result;
        } catch (final Exception e) {

        SecretKey secretKey = new SecretKeySpec(keyClone, algorithm);

        // Store in memory
        sessionKeys.put(sessionId, secretKey);
        rawKeys.put(sessionId, keyClone);

        // Track creation time for rotation (only for non-archived keys)
        if (!sessionId.contains(".v")) {
            keyCreationTimes.put(sessionId, System.currentTimeMillis());
            keyVersions.putIfAbsent(sessionId, 0);

### Feature

- A client-go metric, rest_client_exec_plugin_call_total, has been added to track total calls to client-go credential plugins. ([#98892](https://github.com/kubernetes/kubernetes/pull/98892), [@ankeesler](https://github.com/ankeesler)) [SIG API Machinery, Auth, Cluster Lifecycle and Instrumentation]

* Fix a race condition in the scheduler preemption logic that could cause nominatedNodeName of a pod not to be considered in one or more scheduling cycles. ([#72504](https://github.com/kubernetes/kubernetes/pull/72504), [@bsalamat](https://github.com/bsalamat))

 * all tasks, which minimizes memory footprint but also minimizes concurrency. Instead of choosing
 * either of these extremes, {@code Striped} allows the user to trade between required concurrency
 * and memory footprint. For example, if a set of tasks are CPU-bound, one could easily create a
 * very compact {@code Striped<Lock>} of {@code availableProcessors() * 4} stripes, instead of