response.request().url(), (t2 - t1) / 1e6d, response.headers()));

    return response;
  }
}
```

A call to `chain.proceed(request)` is a critical part of each interceptor’s implementation. This simple-looking method is where all the HTTP work happens, producing a response to satisfy the request. If `chain.proceed(request)` is being called more than once previous response bodies must be closed.

// Copyright (c) 2015-2024 MinIO, Inc.
//
// This file is part of MinIO Object Storage stack
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful

// Copyright (c) 2015-2021 MinIO, Inc.
//
// This file is part of MinIO Object Storage stack
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful

Usando una opción directamente de Starlette puedes declarar un *path parameter* conteniendo un *path* usando una URL como:

```
/files/{file_path:path}
```

En este caso, el nombre del parámetro es `file_path`, y la última parte, `:path`, indica que el parámetro debería coincidir con cualquier *path*.

Así que, puedes usarlo con:

{* ../../docs_src/path_params/tutorial004.py hl[6] *}

/// tip | Consejo

Las variables de entorno pueden ser útiles para manejar **configuraciones** de aplicaciones, como parte de la **instalación** de Python, etc.

## Crear y Usar Variables de Entorno

Puedes **crear** y usar variables de entorno en la **shell (terminal)**, sin necesidad de Python:

//// tab | Linux, macOS, Windows Bash

///

<div class="termy">

```console
$ echo "*" > .venv/.gitignore
```

</div>

/// details | Qué significa ese comando

* `echo "*"`: "imprimirá" el texto `*` en el terminal (la siguiente parte cambia eso un poco)
* `>`: cualquier cosa impresa en el terminal por el comando a la izquierda de `>` no debería imprimirse, sino escribirse en el archivo que va a la derecha de `>`

///

<div class="termy">

```console
$ echo "*" > .venv/.gitignore
```

</div>

/// details | O que esse comando significa

* `echo "*"`: irá "imprimir" o texto `*` no terminal (a próxima parte muda isso um pouco)
* `>`: qualquer coisa impressa no terminal pelo comando à esquerda de `>` não deve ser impressa, mas sim escrita no arquivo que vai à direita de `>`
* `.gitignore`: o nome do arquivo onde o texto deve ser escrito

// Copyright (c) 2015-2021 MinIO, Inc.
//
// This file is part of MinIO Object Storage stack
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful

// Copyright (c) 2015-2021 MinIO, Inc.
//
// This file is part of MinIO Object Storage stack
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful

FastAPI stands on the shoulders of giants:

* <a href="https://www.starlette.io/" class="external-link" target="_blank">Starlette</a> for the web parts.
* <a href="https://docs.pydantic.dev/" class="external-link" target="_blank">Pydantic</a> for the data parts.

## Installation { #installation }