{* ../../docs_src/path_params/tutorial002_py39.py hl[7] *}

In this case, `item_id` is declared to be an `int`.

/// check

This will give you editor support inside of your function, with error checks, completion, etc.

///

## Data <abbr title="also known as: serialization, parsing, marshalling">conversion</abbr> { #data-conversion }

5. Copy the `./app` directory inside the `/code` directory.

    As this has all the code which is what **changes most frequently** the Docker **cache** won't be used for this or any **following steps** easily.

{* ../../docs_src/extending_openapi/tutorial001_py39.py hl[1,4,7:9] *}

### Generate the OpenAPI schema { #generate-the-openapi-schema }

Then, use the same utility function to generate the OpenAPI schema, inside a `custom_openapi()` function:

{* ../../docs_src/extending_openapi/tutorial001_py39.py hl[2,15:21] *}

### Modify the OpenAPI schema { #modify-the-openapi-schema }

#### Union { #union }

You can declare that a variable can be any of **several types**, for example, an `int` or a `str`.

In Python 3.6 and above (including Python 3.10) you can use the `Union` type from `typing` and put inside the square brackets the possible types to accept.

{* ../../docs_src/security/tutorial002_an_py310.py hl[31] *}

Notice that we declare the type of `current_user` as the Pydantic model `User`.

This will help us inside of the function with all the completion and type checks.

/// tip

You might remember that request bodies are also declared with Pydantic models.

Here **FastAPI** won't get confused because you are using `Depends`.

                } catch (ClassNotFoundException e) {
                    // assume it is not assignable from Collection or Map
                }
            }

            messageBuffer.append("Inside the definition for plugin '");
            messageBuffer.append(mojo.getPluginDescriptor().getArtifactId());
            messageBuffer.append("', specify the following:").append(LS).append(LS);

    // We are going to take the project packaging and find all plugins in the default lifecycle and create
    // fully populated Plugin objects, including executions with goals and default configuration taken
    // from the plugin.xml inside a plugin.

    @Override
    public Set<Plugin> getPluginsBoundByDefaultToAllLifecycles(String packaging) {
        if (logger.isDebugEnabled()) {

////

//// tab | Info

... However, quotes inside code snippets must stay as is.

////

## code blocks { #code-blocks }

//// tab | Test

A Bash code example...

```bash
# Print a greeting to the universe
echo "Hello universe"
```

     * are not listed in a user's group membership (e.g. as represented by the
     * tokenGroups constructed attribute retrieved via LDAP).
     *
     * Domain groups nested inside a local group are currently not expanded. In
     * this case the key (SID) type will be SID_TYPE_DOM_GRP rather than
     * SID_TYPE_USER.
     *
     * @param tc
     *            The context to use

But this example is still valid and it shows how to interact with the internal components.

///

We can also use this same approach to access the request body in an exception handler.

All we need to do is handle the request inside a `try`/`except` block:

{* ../../docs_src/custom_request_and_route/tutorial002_an_py310.py hl[14,16] *}