{* ../../docs_src/security/tutorial002_an_py310.py hl[5,12:6] *}

## Create a `get_current_user` dependency { #create-a-get-current-user-dependency }

Let's create a dependency `get_current_user`.

Remember that dependencies can have sub-dependencies?

`get_current_user` will have a dependency with the same `oauth2_scheme` we created before.

///

## Shortcut to remember the names { #shortcut-to-remember-the-names }

Let's see the previous example again:

{* ../../docs_src/response_status_code/tutorial001.py hl[6] *}

`201` is the status code for "Created".

And Pydantic's `Field` returns an instance of `FieldInfo` as well.

`Body` also returns objects of a subclass of `FieldInfo` directly. And there are others you will see later that are subclasses of the `Body` class.

Remember that when you import `Query`, `Path`, and others from `fastapi`, those are actually functions that return special classes.

///

/// tip

{* ../../docs_src/cookie_params/tutorial001_an_py310.py hl[9] *}

/// note | Technical Details

`Cookie` is a "sister" class of `Path` and `Query`. It also inherits from the same common `Param` class.

But remember that when you import `Query`, `Path`, `Cookie` and others from `fastapi`, those are actually functions that return special classes.

///

/// info

{* ../../docs_src/header_params/tutorial001_an_py310.py hl[9] *}

/// note | Technical Details

`Header` is a "sister" class of `Path`, `Query` and `Cookie`. It also inherits from the same common `Param` class.

But remember that when you import `Query`, `Path`, `Header`, and others from `fastapi`, those are actually functions that return special classes.

///

/// info

## Response Status Code { #response-status-code }

You can define the (HTTP) `status_code` to be used in the response of your *path operation*.

You can pass directly the `int` code, like `404`.

But if you don't remember what each number code is for, you can use the shortcut constants in `status`:

{* ../../docs_src/path_operation_configuration/tutorial001_py310.py hl[1,15] *}

///

## Use `Annotated` in the type for the `q` parameter { #use-annotated-in-the-type-for-the-q-parameter }

Remember I told you before that `Annotated` can be used to add metadata to your parameters in the [Python Types Intro](../python-types.md#type-hints-with-metadata-annotations){.internal-link target=_blank}?

loop` when integrating asynchronous function calls in your tests (e.g. when using <a href="https://stackoverflow.com/questions/41584243/runtimeerror-task-attached-to-a-different-loop" class="external-link" target="_blank">MongoDB's MotorClient</a>), remember to instantiate objects that need an event loop only within async functions, e.g. an `'@app.on_event("startup")` callback.

///...

   * calls to Builder.put (though we don't really care *which* two values if there were more than
   * two). These considerations lead us to have a field of type DuplicateKey in the Builder, which
   * will remember the first duplicate key we encountered. All later calls to buildOrThrow() can
   * mention that key with its values. Further duplicates might be added in the meantime but since

Create file parameters the same way you would for `Body` or `Form`:

{* ../../docs_src/request_files/tutorial001_an_py39.py hl[9] *}

/// info

`File` is a class that inherits directly from `Form`.

But remember that when you import `Query`, `Path`, `File` and others from `fastapi`, those are actually functions that return special classes.

///

/// tip