openapi-generator package name and version

I'm using the openapi-generator-maven-plugin to generate a python-pydantic-v1 client against my spec file. The generation is working well, but the generated setup.py script has default package name and version values, no matter what settings I configure in the plugin in my pom file. I can see that the mustache file for the setup.py script is using certain template parameters for these values, but changing them in the plugin configuration seems to have no effect on the values of these template parameters. 

Any thoughts would be much appreciated.

Thanks in advance, John.