* variance</a> of the values. The count must be non-zero.
   *
   * <p>This is guaranteed to return zero if the dataset contains only exactly one finite value. It
   * is not guaranteed to return zero when the dataset consists of the same value multiple times,
   * due to numerical errors. However, it is guaranteed never to return a negative result.
   *

  (
    pushd "${DASHBOARDS}" > /dev/null
    jb install
    for file in *.libsonnet; do
      dashboard="${file%.*}"
      jsonnet -J vendor -J lib "${file}" > "${dashboard}-dashboard.gen.json"
    done
  )
  helm3 template grafana grafana \
    --namespace istio-system \
    --version "${GRAFANA_VERSION}" \
    --repo https://grafana.github.io/helm-charts \
    -f "${WD}/values-grafana.yaml"

 *  Fix: Don't crash with a `InaccessibleObjectException` when detecting the platform trust manager
    on Java 17+.
 *  Fix: Don't crash if a cookie's value is a lone double quote character.
 *  Fix: Don't crash when canceling an event source created by `EventSources.processResponse()`.
 *  New: `Cache` now has a public constructor that takes an [okio.FileSystem]. This should make it

以如下方式调用：

```Python
print(user_dict)
```

输出的就是 Python **字典**：

```Python
{
    'username': 'john',
    'password': 'secret',
    'email': '******@****.***',
    'full_name': None,
}
```

#### 解包 `dict`

把**字典** `user_dict` 以 `**user_dict` 形式传递给函数（或类），Python 会执行**解包**操作。它会把 `user_dict` 的键和值作为关键字参数直接传递。

因此，接着上面的 `user_dict` 继续编写如下代码：

```Python
UserInDB(**user_dict)
```

	wg.Add(2)
	go func() {
		defer wg.Done()
		srcSize, err := io.Copy(srcSha256, sobj)
		if err != nil {
			fmt.Printf("unreadable on source: %s (%s)\n", srcCtnt.Key, err)
			sourceFailed = true
		} else if srcSize != srcCtnt.Size {
			fmt.Printf("unreadable on source - size differs upon read: %s\n", srcCtnt.Key)
			sourceFailed = true
		}
	}()
	go func() {
		defer wg.Done()
		tgtSize, err := io.Copy(tgtSha256, tobj)

  }

  /**
   * Invokes {@code future.}{@link Future#get() get()} uninterruptibly.
   *
   * <p>Similar methods:
   *
   * <ul>
   *   <li>To retrieve a result from a {@code Future} that is already done, use {@link
   *       Futures#getDone Futures.getDone}.
   *   <li>To treat {@link InterruptedException} uniformly with other exceptions, use {@link
   *       Futures#getChecked(Future, Class) Futures.getChecked}.

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *