They are replaced in Maven 4 with Maven 4 API Core's {{{../../api/maven-api-core/apidocs/org/apache/maven/api/Type.html}Dependency Types}},
  with default values defined in {{{../../compat/maven-resolver-provider/apidocs/org/apache/maven/repository/internal/type/DefaultTypeProvider.html}DefaultTypeProvider}}.

  For compatibility, legacy Maven 3 artifact handlers are still provided:

 * specific language governing permissions and limitations
 * under the License.
 */
package org.apache.maven.repository;

import java.util.List;
import java.util.Map;
import java.util.Set;

import org.apache.maven.artifact.Artifact;
import org.apache.maven.artifact.repository.ArtifactRepository;

/**
 *
 *
 *
 */
@Deprecated
public class MetadataResolutionRequest {

/// 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 }

            <?xml version="1.0" encoding="UTF-8"?>
            <project xmlns="http://maven.apache.org/POM/4.0.0">
                <modelVersion>4.0.0</modelVersion>
                <groupId>test</groupId>
                <artifactId>test</artifactId>
                <version>1.0.0</version>
                <properties>
                    <maven.compiler.source>17</maven.compiler.source>
                </properties>
            </project>

 */
package org.apache.maven.cling;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

import org.apache.maven.api.annotations.Nullable;
import org.apache.maven.api.cli.Invoker;
import org.apache.maven.api.cli.Parser;
import org.apache.maven.api.cli.ParserRequest;
import org.apache.maven.cling.invoker.ProtoLookup;
import org.apache.maven.cling.invoker.mvnenc.EncryptInvoker;

 */
package org.apache.maven.cling;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

import org.apache.maven.api.annotations.Nullable;
import org.apache.maven.api.cli.Invoker;
import org.apache.maven.api.cli.Parser;
import org.apache.maven.api.cli.ParserRequest;
import org.apache.maven.cling.invoker.ProtoLookup;
import org.apache.maven.cling.invoker.mvnsh.ShellInvoker;

 * under the License.
 */
package org.apache.maven.repository.legacy.resolver.transform;

import javax.inject.Named;
import javax.inject.Singleton;

import org.apache.maven.artifact.Artifact;
import org.apache.maven.artifact.metadata.ArtifactMetadata;
import org.apache.maven.artifact.repository.ArtifactRepository;
import org.apache.maven.artifact.repository.RepositoryRequest;

    <groupId>maven-t06</groupId>
    <version>1.0</version>
  </parent>
  <modelVersion>4.0.0</modelVersion>
  <groupId>maven-t06</groupId>
  <artifactId>p1</artifactId>
  <packaging>pom</packaging>
  <name>p1</name>
  <version>1.0</version>
  <scm>
    <url>scm-url</url>
  </scm>
  <dependencyManagement>
    <dependencies>
      <dependency>
        <groupId>maven-test</groupId>

Let's say you have a file structure as described in [Bigger Applications](bigger-applications.md){.internal-link target=_blank}:

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

In the file `main.py` you have your **FastAPI** app:


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

### Testing file { #testing-file }

        static class DiInjected {
            @org.apache.maven.api.di.Inject
            ModelParser parser;

            @org.apache.maven.api.di.Inject
            List<ModelParser> parsers;

            @org.apache.maven.api.di.Inject
            Map<String, ModelParser> parsersMap;
        }

        @org.apache.maven.api.di.Named
        @org.apache.maven.api.di.Singleton