---

/// tip

Nếu bạn sử dụng Python 3.9 hoặc lớn hơn, bạn không phải import `List` từ `typing`, bạn có thể sử dụng `list` để thay thế.

///

Bằng cách này, trình soạn thảo của bạn có thể hỗ trợ trong khi xử lí các phần tử trong danh sách:

<img src="/img/python-types/image05.png">

Đa phần đều không thể đạt được nếu không có các kiểu dữ liệu.

Chú ý rằng, biến `item` là một trong các phần tử trong danh sách `items`.

    ...
```

But right at the moment Python compares the first `j` in `johndoe` to the first `s` in `stanleyjobson`, it will return `False`, because it already knows that those two strings are not the same, thinking that "there's no need to waste more computation comparing the rest of the letters". And your application will say "Incorrect username or password".

But then the attackers try with username `stanleyjobsox` and password `love123`.

Now that we have **multiple models**, we can update the parts of the app that use them.

We receive in the request a `HeroCreate` *data model*, and from it, we create a `Hero` *table model*.

This new *table model* `Hero` will have the fields sent by the client, and will also have an `id` generated by the database.

* the data from the client to be sent through the network
* the data sent by your program to be received by the client through the network
* the contents of a file in the disk to be read by the system and given to your program
* the contents your program gave to the system to be written to disk
* a remote API operation

To achieve this, the `:80`-backend must have a list of "allowed origins".

In this case, the list would have to include `http://localhost:8080` for the `:8080`-frontend to work correctly.

## Wildcards

/// tip

Prefer to use the `Annotated` version if possible.

///

```Python hl_lines="7-9  13"
{!> ../../docs_src/request_form_models/tutorial001.py!}
```

////

**FastAPI** will **extract** the data for **each field** from the **form data** in the request and give you the Pydantic model you defined.

## Check the Docs

You can verify it in the docs UI at `/docs`:

<div class="screenshot">

* It can then do something to that **request** or run any needed code.
* Then it passes the **request** to be processed by the rest of the application (by some *path operation*).
* It then takes the **response** generated by the application (by some *path operation*).
* It can do something to that **response** or run any needed code.
* Then it returns the **response**.

/// note | "Technical Details"

/// info

Notice how `Offer` has a list of `Item`s, which in turn have an optional list of `Image`s

///

## Bodies of pure lists

If the top level value of the JSON body you expect is a JSON `array` (a Python `list`), you can declare the type in the parameter of the function, the same as in Pydantic models:

```Python
images: List[Image]
```

or in Python 3.9 and above:

```Python
images: list[Image]

But then you have to call "that method that converts the first letter to upper case".

Was it `upper`? Was it `uppercase`? `first_uppercase`? `capitalize`?

Then, you try with the old programmer's friend, editor autocompletion.

You type the first parameter of the function, `first_name`, then a dot (`.`) and then hit `Ctrl+Space` to trigger the completion.