En este caso, es el `str`:

```Python
"{$callback_url}/invoices/{$request.body.id}"
```

Entonces, si el usuario de tu API (el desarrollador externo) envía un request a *tu API* a:

```
https://yourapi.com/invoices/?callback_url=https://www.external.org/events
```

con un JSON body de:

```JSON
{
    "id": "2expen51ve",
    "customer": "Mr. Richie Rich",
    "total": "9999"
}
```

def main(user_id: str):
    return user_id


# Модель Pydantic
class User(BaseModel):
    id: int
    name: str
    joined: date
```

Далі це можна використовувати так:

```Python
my_user: User = User(id=3, name="John Doe", joined="2018-07-19")

second_user_data = {
    "id": 4,
    "name": "Mary",
    "joined": "2018-11-30",
}

my_second_user: User = User(**second_user_data)
```

    public static final String ERRORS_failed_to_delete_file = "{errors.failed_to_delete_file}";

    /** The key of the message: Doc ID is not found. Cause: {0} */
    public static final String ERRORS_docid_not_found = "{errors.docid_not_found}";

    /** The key of the message: The URL for the document ID is not found. Cause: {0} */
    public static final String ERRORS_document_not_found = "{errors.document_not_found}";

 * source of bugs and confusion.
 *
 * <p><b>Note:</b> every {@link ImmutableMultimap} offers an {@link #inverse} view, so there is no
 * need for a distinct {@code ImmutableBiMultimap} type.
 *
 * <p><a id="iteration"></a>
 *
 * <p><b>Key-grouped iteration.</b> All view collections follow the same iteration order. In all
 * current implementations, the iteration order always keeps multiple entries with the same key

 * conventional bounded queues, which either block or reject new elements when full.
 *
 * <p>This implementation is based on the <a
 * href="http://portal.acm.org/citation.cfm?id=6621">min-max heap</a> developed by Atkinson, et al.
 * Unlike many other double-ended priority queues, it stores elements in a single array, as compact
 * as the traditional heap data structure used in {@link PriorityQueue}.
 *

// Returns the device type of the operation that produced `h`.
TF_CAPI_EXPORT extern const char* TFE_TensorHandleDeviceType(
    TFE_TensorHandle* h, TF_Status* status);

// Returns the device ID of the operation that produced `h`.
TF_CAPI_EXPORT extern int TFE_TensorHandleDeviceID(TFE_TensorHandle* h,
                                                   TF_Status* status);

chrome.omnibox.onInputEntered.addListener(function(t) {
  var url = urlForInput(t);
  if (url) {
    chrome.tabs.query({ "active": true, "currentWindow": true }, function(tab) {
      if (!tab) return;
      chrome.tabs.update(tab.id, { "url": url, "selected": true });
    });
  }

labels.excludedPaths=Исключенные пути для сканирования
labels.excludedUrls=Исключенные URL для сканирования
labels.excludedDocPaths=Исключенные пути для поиска
labels.excludedDocUrls=Исключенные URL для поиска
labels.hostname=Имя хоста
labels.id=ID
labels.includedPaths=Включенные пути для сканирования
labels.includedUrls=Включенные URL для сканирования
labels.includedDocPaths=Включенные пути для поиска
labels.includedDocUrls=Включенные URL для поиска

            },
            "Item": {
                "title": "Item",
                "required": [
                    "id",
                    "value"
                ],
                "type": "object",
                "properties": {
                    "id": {
                        "title": "Id",
                        "type": "string"
                    },
                    "value": {

            if (parentData == null) {
                currentData = superData;
            } else if (currentData == resultData) { // First iteration - add initial id after version resolution.
                currentData.setGroupId(
                        currentData.getRawModel().getGroupId() == null
                                ? parentData.getGroupId()