necessary <inherits> lines for c.g.c.collect.testModule, etc. However, adding <inherits>
            lines could make c.g.c.base.testModule transitively inherit from extra modules. If some
            of those modules are ones that it uses but forgets to list in its own <inherits>, we'd
            like to get an error. Currently we do, but if we add the extra <inherits> lines, we
            won't.

    !!! tip
        Prefer to use the `Annotated` version if possible.

    ```Python hl_lines="7"
    {!> ../../../docs_src/request_files/tutorial001.py!}
    ```

!!! 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

		}
		if retentionPermErr != ErrNone {
			return mode, retainDate, legalHold, retentionPermErr
		}
		return rMode, rDate, legalHold, ErrNone
	}
	if replica { // replica inherits retention metadata only from source
		return "", objectlock.RetentionDate{}, legalHold, ErrNone
	}
	if !retentionRequested && retentionCfg.Validity > 0 {
		if retentionPermErr != ErrNone {

```Python hl_lines="1"
{!../../../docs_src/first_steps/tutorial001.py!}
```

`FastAPI` is a Python class that provides all the functionality for your API.

!!! note "Technical Details"
    `FastAPI` is a class that inherits directly from `Starlette`.

    You can use all the <a href="https://www.starlette.io/" class="external-link" target="_blank">Starlette</a> functionality with `FastAPI` too.

### Step 2: create a `FastAPI` "instance"

How does this work? Let's check that out. 🤓

### Type Annotations and Tooling

First let's see how editors, mypy and other tools would see this.

`BaseUser` has the base fields. Then `UserIn` inherits from `BaseUser` and adds the `password` field, so, it will include all the fields from both models.

We annotate the function return type as `BaseUser`, but we are actually returning a `UserIn` instance.

!!! check "**FastAPI** uses it to"
    Handle all the core web parts. Adding features on top.

    The class `FastAPI` itself inherits directly from the class `Starlette`.

    So, anything that you can do with Starlette, you can do it directly with **FastAPI**, as it is basically Starlette on steroids.

				"Unable to validate credentials inherited from the secret file(s)")
		}
		if accessKey != "" {
			os.Setenv(config.EnvRootUser, accessKey)
		}
	}

	if env.IsSet(config.EnvSecretKeyFile) {
		secretKey, err := readFromSecret(env.Get(config.EnvSecretKeyFile, ""))
		if err != nil {
			logger.Fatal(config.ErrInvalidCredentials(err),
				"Unable to validate credentials inherited from the secret file(s)")
		}

                if (fessConfig.isResultCollapsed()) {
                    final Map<String, SearchHits> innerHits = searchHit.getInnerHits();
                    if (innerHits != null) {
                        final SearchHits innerSearchHits = innerHits.get(fessConfig.getQueryCollapseInnerHitsName());
                        if (innerSearchHits != null) {

import static com.google.common.truth.Truth.assertThat;
import static org.junit.Assert.assertThrows;

import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Sets;
import java.lang.annotation.Inherited;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.reflect.Method;
import java.util.Collections;
import java.util.Set;
import junit.framework.TestCase;

/**

import static com.google.common.truth.Truth.assertThat;
import static org.junit.Assert.assertThrows;

import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Sets;
import java.lang.annotation.Inherited;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.reflect.Method;
import java.util.Collections;
import java.util.Set;
import junit.framework.TestCase;

/**