<div class="termy">

```console
// Here we don't set the env var yet
$ python main.py

// As we didn't set the env var, we get the default value

Hello World from Python

// But if we create an environment variable first
$ export MY_NAME="Wade Wilson"

// And then call the program again
$ python main.py

// Now it can read the environment variable

Hello Wade Wilson from Python
```

maven-core-it file:///${basedir}/repo true true . pom.xml src/** src/main/resources src/main/java/org/apache/maven/its/mng3906/SomeClass.java src/main/java/org/apache/maven/its/mng3906/SomeClass.java package org.apache.maven.its.mng3906; public class SomeClass { } META-INF/maven/org.apache.maven.its.mng3906/e/pom.xml 4.0.0 org.apache.maven.its.mng3906 e 0.1 jar maven-core-it file:///${basedir}/repo true true . pom.xml src/** src/main/resources META-INF/maven/org.apache.maven.its.mng3906/e/pom.properties...

 *     <li>{@linkplain Project#getPomArtifact() the project POM artifact}</li>
 *     <li>{@linkplain Project#getMainArtifact() the main artifact}</li>
 *     <li>{@linkplain org.apache.maven.api.services.ProjectManager#attachArtifact(Session, Project, Path) artifacts to be attached to a project}</li>
 * </ul>
 *
 * <p>For the main artifact and attached artifacts, the
 * {@link org.apache.maven.api.services.ArtifactManager ArtifactManager} service must be used

        // /tmp/junit-16591192886395443631/.m2/extensions.xml:3
        // [main] WARNING org.apache.maven.cling.invoker.PlexusContainerCapsuleFactory -
        // [main] WARNING org.apache.maven.cling.invoker.PlexusContainerCapsuleFactory - Order of core extensions
        // precedence is project > user > installation. Selected extensions are:
        // [main] WARNING org.apache.maven.cling.invoker.PlexusContainerCapsuleFactory - *

     * circumstances.
     */
    public static void main(String[] args) throws IOException {
        int exitCode = new MavenCling().run(args, null, null, null, false);
        System.exit(exitCode);
    }

    /**
     * ClassWorld Launcher "enhanced" entry point: returning exitCode and accepts Class World.
     */
    public static int main(String[] args, ClassWorld world) throws IOException {

## Call `uvicorn` { #call-uvicorn }

In your FastAPI application, import and run `uvicorn` directly:

{* ../../docs_src/debugging/tutorial001_py39.py hl[1,15] *}

### About `__name__ == "__main__"` { #about-name-main }

The main purpose of the `__name__ == "__main__"` is to have some code that is executed when your file is called with:

<div class="termy">

```console
$ python myapp.py
```

</div>

        "platforms/documentation/docs/src/docs/release/release-notes-assets/",
        "subprojects/launcher/src/main/resources/release-features.txt",
        "platforms/core-runtime/launcher/src/main/resources/release-features.txt"
    ]

    static void main(String[] args) {
        if (args.length != 1) {
            System.err.println("Usage: groovy CheckBadMerge.groovy <commits_file>")

```
.
├── app
│   ├── __init__.py
│   ├── main.py
│   └── test_main.py
```

El archivo `main.py` tendría:

{* ../../docs_src/async_tests/app_a_py39/main.py *}

El archivo `test_main.py` tendría los tests para `main.py`, podría verse así ahora:

{* ../../docs_src/async_tests/app_a_py39/test_main.py *}

## Ejecútalo { #run-it }

   <span style="background-color:#007166"><font color="#D3D7CF"> module </font></span>  🐍 main.py

     <span style="background-color:#007166"><font color="#D3D7CF"> code </font></span>  Importing the FastAPI app object from the module with the
             following code:

   <span style="background-color:#007166"><font color="#D3D7CF"> module </font></span>  🐍 main.py

     <span style="background-color:#007166"><font color="#D3D7CF"> code </font></span>  Importing the FastAPI app object from the module with the
             following code: