}

    @Override
    public String toString() {
        return render("");
    }

    public String render(String indentation) {
        if (messages.isEmpty()) {
            return indentation + "There were no validation errors.";
        }

        StringBuilder message = new StringBuilder();
        for (int i = 0; i < messages.size(); i++) {
            message.append(indentation)
                    .append('[')

- `main.py` নামে একটি ফাইল তৈরি করুন:

```Python
from typing import Union

from fastapi import FastAPI

app = FastAPI()


@app.get("/")
def read_root():
    return {"Hello": "World"}


@app.get("/items/{item_id}")
def read_item(item_id: int, q: Union[str, None] = None):
    return {"item_id": item_id, "q": q}
```

<details markdown="1">

```Python
from typing import Union

from fastapi import FastAPI

app = FastAPI()


@app.get("/")
def read_root():
    return {"Hello": "World"}


@app.get("/items/{item_id}")
def read_item(item_id: int, q: Union[str, None] = None):
    return {"item_id": item_id, "q": q}
```

<details markdown="1">

      ImmutableMap.<String, String>builder()
          .put("empty", "")
          .put("1 char", "0")
          .put("1 word", "hello")
          .put("2 words", "hello world")
          .put("\\n line break", "hello\nworld")
          .put("\\r line break", "hello\rworld")
          .put("\\r\\n line break", "hello\r\nworld")
          .put("\\n at EOF", "hello\nworld\n")

Create a file `main.py` with:

```Python
from typing import Union

from fastapi import FastAPI

app = FastAPI()


@app.get("/")
def read_root():
    return {"Hello": "World"}


@app.get("/items/{item_id}")
def read_item(item_id: int, q: Union[str, None] = None):
    return {"item_id": item_id, "q": q}
```

<details markdown="1">

{* ../../docs_src/custom_response/tutorial009c.py hl[9:14,17] *}

Now instead of returning:

```json
{"message": "Hello World"}
```

...this response will return:

```json
{
  "message": "Hello World"
}
```

Of course, you will probably find much better ways to take advantage of this than formatting JSON. 😉

 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package okhttp3.internal.connection

/**
 * Used when we were unsuccessful in the planning phase of a connection:
 *
 *  * A DNS lookup failed
 *  * The configuration is incapable of carrying the request, such as when the client is configured

    // it.
    executeListener(runnable, executor);
  }

  /**
   * Runs this execution list, executing all existing pairs in the order they were added. However,
   * note that listeners added after this point may be executed before those previously added, and
   * note that the execution order of all listeners is ultimately chosen by the implementations of

* Buat file `main.py` dengan:

```Python
from typing import Union

from fastapi import FastAPI

app = FastAPI()


@app.get("/")
def read_root():
    return {"Hello": "World"}


@app.get("/items/{item_id}")
def read_item(item_id: int, q: Union[str, None] = None):
    return {"item_id": item_id, "q": q}
```

<details markdown="1">

```Python
from typing import Union

from fastapi import FastAPI

app = FastAPI()


@app.get("/")
def read_root():
    return {"Hello": "World"}


@app.get("/items/{item_id}")
def read_item(item_id: int, q: Union[str, None] = None):
    return {"item_id": item_id, "q": q}
```

<details markdown="1">