* href="http://en.wikipedia.org/wiki/Null_Object_pattern">null object</a> for the type in question.
 *
 * <p>This class is not intended as a direct analogue of any existing "option" or "maybe" construct
 * from other programming environments, though it may bear some similarities.
 *
 * <p>An instance of this class is serializable if its reference is absent or is a serializable
 * object.
 *

Stellen Sie sicher, dass Sie eine [virtuelle Umgebung](../virtual-environments.md){.internal-link target=_blank} erstellen, sie aktivieren und es dann installieren, zum Beispiel:

```console
$ pip install email-validator
```

oder mit:

```console
$ pip install "pydantic[email]"

## Установка `SQLModel` { #install-sqlmodel }

Сначала убедитесь, что вы создали [виртуальное окружение](../virtual-environments.md){.internal-link target=_blank}, активировали его и затем установили `sqlmodel`:

<div class="termy">

```console
$ pip install sqlmodel
---> 100%
```

</div>

            method.setAccessible(true);
          } catch (AccessControlException e) {
            // OK: the method is accessible to us anyway. The setAccessible call is only for
            // unusual execution environments where that might not be true.
          }
          builder.put(method.getName(), method);
        }
      }
      typeVariableMethods = builder.buildKeepingLast();
    }

## Instalar `SQLModel` { #install-sqlmodel }

Primero, asegúrate de crear tu [entorno virtual](../virtual-environments.md){.internal-link target=_blank}, actívalo, y luego instala `sqlmodel`:

<div class="termy">

```console
$ pip install sqlmodel
---> 100%
```

</div>

Para usar `EmailStr`, primero instala <a href="https://github.com/JoshData/python-email-validator" class="external-link" target="_blank">`email-validator`</a>.

Asegúrate de crear un [entorno virtual](../virtual-environments.md){.internal-link target=_blank}, activarlo, y luego instalarlo, por ejemplo:

```console
$ pip install email-validator
```

o con:

```console
$ pip install "pydantic[email]"
```

///

* <a href="https://docs.pydantic.dev/" class="external-link" target="_blank">Pydantic</a> para las partes de datos.

## Instalación { #installation }

Crea y activa un <a href="https://fastapi.tiangolo.com/es/virtual-environments/" class="external-link" target="_blank">entorno virtual</a> y luego instala FastAPI:

<div class="termy">

```console
$ pip install "fastapi[standard]"

---> 100%
```

</div>

* <a href="https://docs.pydantic.dev/" class="external-link" target="_blank">Pydantic</a> para a parte de dados.

## Instalação { #installation }

Crie e ative um <a href="https://fastapi.tiangolo.com/pt/virtual-environments/" class="external-link" target="_blank">ambiente virtual</a> e então instale o FastAPI:

<div class="termy">

```console
$ pip install "fastapi[standard]"

---> 100%
```

</div>

## Installation { #installation }

Create and activate a <a href="https://fastapi.tiangolo.com/virtual-environments/" class="external-link" target="_blank">virtual environment</a> and then install FastAPI:

<div class="termy">

```console
$ pip install "fastapi[standard]"

---> 100%
```

</div>

## Installation

Create and activate a <a href="https://fastapi.tiangolo.com/virtual-environments/" class="external-link" target="_blank">virtual environment</a> and then install FastAPI:

<div class="termy">

```console
$ pip install "fastapi[standard]"

---> 100%
```

</div>