all `OkHttpClient` instances shared a common connection pool by default.
    In OkHttp 3.x, each new `OkHttpClient` gets its own private connection pool.
    Applications should avoid creating many connection pools as doing so
    prevents connection reuse. Each connection pool holds its own set of
    connections alive so applications that have many pools also risk exhausting
    memory!

{* ../../docs_src/query_params_str_validations/tutorial015_an_py310.py ln[16:19] hl[17] *}

#### A Random Item { #a-random-item }

With `data.items()` we get an <abbr title="Something we can iterate on with a for loop, like a list, set, etc.">iterable object</abbr> with tuples containing the key and value for each dictionary item.

import com.google.common.annotations.J2ktIncompatible;
import java.io.Serializable;
import java.util.NoSuchElementException;
import org.jspecify.annotations.Nullable;

/**
 * Implementation detail for the internal structure of {@link Range} instances. Represents a unique
 * way of "cutting" a "number line" (actually of instances of type {@code C}, not necessarily

            assertEquals(status, echoResponse.getErrorCode());
        }
    }

    @Nested
    @DisplayName("Signed Flag Tests")
    class SignedFlagTests {

        @Test
        @DisplayName("Should detect signed flag")
        void testIsSigned() {
            assertFalse(echoResponse.isSigned());

            echoResponse.addFlags(ServerMessageBlock2.SMB2_FLAGS_SIGNED);

Eğer tarayıcınızda <a href="http://127.0.0.1:8000/items/foo" class="external-link" target="_blank">http://127.0.0.1:8000/items/foo</a> sayfasını açarsanız, şuna benzer güzel bir HTTP hatası ile karşılaşırsınız:

```JSON
{
  "detail": [
    {
      "type": "int_parsing",
      "loc": [
        "path",
        "item_id"
      ],
      "msg": "Input should be a valid integer, unable to parse string as an integer",
      "input": "foo"
    }

Якщо ж відкрити у браузері посилання <a href="http://127.0.0.1:8000/items/foo" class="external-link" target="_blank">http://127.0.0.1:8000/items/foo</a>, то побачимо цікаву HTTP-помилку:

```JSON
{
  "detail": [
    {
      "type": "int_parsing",
      "loc": [
        "path",
        "item_id"
      ],
      "msg": "Input should be a valid integer, unable to parse string as an integer",
      "input": "foo"
    }

ここで、クエリパラメータ `needy` は `str` 型の必須のクエリパラメータです

以下のURLをブラウザで開くと:

```
http://127.0.0.1:8000/items/foo-item
```

...必須のパラメータ `needy` を加えなかったので、以下の様なエラーが表示されます:

```JSON
{
    "detail": [
        {
            "loc": [
                "query",
                "needy"
            ],
            "msg": "field required",
            "type": "value_error.missing"
        }
    ]
}

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      defend, and hold each Contributor harmless for any liability
      incurred by, or claims asserted against, such Contributor by reason
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