# - 25 for running Javadoc and javac (to help people who build Guava locally and might not use a recent JDK to run Maven)
      - name: 'Set up JDKs'
        uses: actions/setup-java@dded0888837ed1f317902acf8a20df0ad188d165 # v5.0.0
        with:
          java-version: |
            ${{ matrix.java }}
            25

{* ../../docs_src/pydantic_v1_in_v2/tutorial002_an_py310.py hl[2,5,15] *}

/// warning

Have in mind that as the Pydantic team no longer supports Pydantic v1 in recent versions of Python, starting from Python 3.14, using `pydantic.v1` is also not supported in Python 3.14 and above.

///

### Pydantic v1 and v2 on the same app { #pydantic-v1-and-v2-on-the-same-app }

### `startup` event { #startup-event }

To add a function that should be run before the application starts, declare it with the event `"startup"`:

{* ../../docs_src/events/tutorial001_py39.py hl[8] *}

In this case, the `startup` event handler function will initialize the items "database" (just a `dict`) with some values.

You can add more than one event handler function.

```console
$ python -m ensurepip --upgrade

---> 100%
```

</div>

This command will install pip if it is not already installed and also ensures that the installed version of pip is at least as recent as the one available in `ensurepip`.

///

## Add `.gitignore` { #add-gitignore }

If you are using **Git** (you should), add a `.gitignore` file to exclude everything in your `.venv` from Git.

/// tip

<div class="termy">

```console
$ cd ~/code/prisoner-of-azkaban

$ python main.py

// Error importing sirius, it's not installed 😱
Traceback (most recent call last):
    File "main.py", line 1, in <module>
        import sirius
```

</div>

As Python advances, **newer versions** come with improved support for these type annotations and in many cases you won't even need to import and use the `typing` module to declare the type annotations.

If you can choose a more recent version of Python for your project, you will be able to take advantage of that extra simplicity.

In all the docs there are examples compatible with each version of Python (when there's a difference).

     * The mojo started event is also captured to determine the lifecycle
     * phases the project has been through.
     *
     * @param event the execution event
     */
    private void processEvent(ExecutionEvent event) {
        MavenProject project = event.getProject();
        switch (event.getType()) {
            case MojoStarted:
                String phase = event.getMojoExecution().getLifecyclePhase();

<div class="termy">

```console
$ cd ~/code/prisoner-of-azkaban

$ python main.py

// Fehler beim Importieren von sirius, es ist nicht installiert 😱
Traceback (most recent call last):
    File "main.py", line 1, in <module>
        import sirius
```

</div>

     * {@code expectedValuesPerKey} is a good estimate.
     *
     * <p>This may be called more than once; each newly added key will use the most recent call to
     * {@link #expectedValuesPerKey} as its hint.
     *
     * @throws IllegalArgumentException if {@code expectedValuesPerKey} is negative
     * @since 33.3.0
     */
    @CanIgnoreReturnValue

     * {@code expectedValuesPerKey} is a good estimate.
     *
     * <p>This may be called more than once; each newly added key will use the most recent call to
     * {@link #expectedValuesPerKey} as its hint.
     *
     * @throws IllegalArgumentException if {@code expectedValuesPerKey} is negative
     * @since 33.3.0
     */
    @CanIgnoreReturnValue