| `io_read_bytes`               | `counter` | Total bytes read by the process from the underlying storage system, /proc/[pid]/io read_bytes                  | `server` |
| `io_wchar_bytes`              | `counter` | Total bytes written by the process to the underlying storage system including page cache, /proc/[pid]/io wchar | `server` |

  # Retrieve Envoy server metrics in prometheus format with custom proxy admin port
  istioctl experimental envoy-stats <pod-name[.namespace]> --output prom --proxy-admin-port 15000

  # Retrieve Envoy server metrics in prometheus format with merged application metrics
  istioctl experimental envoy-stats <pod-name[.namespace]> --output prom-merged

  # Retrieve Envoy cluster metrics

                // E.g., coreR.string.hello
                //   -> string.hello (drop the first segment)
                //   test.pkg.R.string.hello
                //   -> string.hello (take last two segments, where the size is determined by the size of qualified access minus 1)
                val fixedQualifiedAccessSegments = qualifiedAccessSegments.drop(1)

In that case, you can simply swap the standard `dataclasses` with `pydantic.dataclasses`, which is a drop-in replacement:

```{ .python .annotate hl_lines="1  5  8-11  14-17  23-25  28" }
{!../../../docs_src/dataclasses/tutorial003.py!}
```

1. We still import `field` from standard `dataclasses`.

2. `pydantic.dataclasses` is a drop-in replacement for `dataclasses`.

3. The `Author` dataclass includes a list of `Item` dataclasses.

		t.Fatalf("Failed to drop view, got %v", err)
	}

	query = DB.Model(&User{}).Where("age > ?", 20)
	if err := DB.Migrator().CreateView("users_view", gorm.ViewOption{Query: query}); err != nil {
		t.Fatalf("Failed to crate view, got %v", err)
	}
	if err := DB.Migrator().DropView("users_view"); err != nil {
		t.Fatalf("Failed to drop view, got %v", err)
	}
}

}

class IanaSuites(
  val name: String,
  val suites: List<SuiteId>,
) {
  fun fromJavaName(javaName: String): SuiteId {
    return suites.firstOrNull {
      it.name == javaName || it.name == "TLS_${javaName.drop(4)}"
    } ?: throw IllegalArgumentException("No such suite: $javaName")
  }
}

suspend fun fetchIanaSuites(okHttpClient: OkHttpClient): IanaSuites {

    }


def test_create_item_bad_token():
    response = client.post(
        "/items/",
        headers={"X-Token": "hailhydra"},
        json={"id": "bazz", "title": "Bazz", "description": "Drop the bazz"},
    )
    assert response.status_code == 400
    assert response.json() == {"detail": "Invalid X-Token header"}


def test_create_existing_item():
    response = client.post(
        "/items/",

    }


def test_create_item_bad_token():
    response = client.post(
        "/items/",
        headers={"X-Token": "hailhydra"},
        json={"id": "bazz", "title": "Bazz", "description": "Drop the bazz"},
    )
    assert response.status_code == 400
    assert response.json() == {"detail": "Invalid X-Token header"}


def test_create_existing_item():
    response = client.post(
        "/items/",

  // namespace is associated with the "environment" of "prod" or "staging";
  // you will set the selector as follows:
  // "namespaceSelector": {
  //   "matchExpressions": [
  //     {
  //       "key": "environment",
  //       "operator": "In",
  //       "values": [
  //         "prod",
  //         "staging"
  //       ]
  //     }
  //   ]
  // }
  //

    }


def test_create_item_bad_token():
    response = client.post(
        "/items/",
        headers={"X-Token": "hailhydra"},
        json={"id": "bazz", "title": "Bazz", "description": "Drop the bazz"},
    )
    assert response.status_code == 400
    assert response.json() == {"detail": "Invalid X-Token header"}


def test_create_existing_item():
    response = client.post(
        "/items/",