async def METHOD_NAME(prefect_base_image: str):
    packager = DockerPackager(
        base_image=prefect_base_image,
        python_environment=PythonEnvironment(
            python_version="3.9",
            pip_requirements=["requests==2.28.0"],
        ),
    )
    manifest = await packager.package(howdy)
    assert isinstance(manifest, DockerPackageManifest)
    assert IMAGE_ID_PATTERN.match(manifest.image)
    assert manifest.image_flow_location == "/flow.py"
    assert manifest.flow_name == "howdy"