If you wish to contribute to async_upnp_client, then thank you! You can create a create a pull request with your changes. Create your pull request(s) against the development branch.
Changes are recorded using towncrier. Please do include change-files in your pull requests. To create a new change-file you can run:
$ towncrier create <pr_number>.feature # This creates a change-file for a new feature. # towncrier create <pr_number>.bugfix # This creates a change-file for a bugfix.
After creating the file, you can edit the created file.