The following Pull Request:

• Closes issue add project.toml file #305
• Also closes namespace_packages deprecated #277. In closing this issue, I had to make some modificiations to allow for namespaces and package recovery (which is now implicit). That meant:
• Removed __init__.py file within src/pydap/handlers/. For more information about this about namespaces and package recovery.
• A new feature is added. It is now easy to print pydap's version (which is inferred from commits).
• A test is included to read the version number.

As described in #305, much of the functionality of setup.py has been deprecated and at the very least there should always be an pyproject.toml file. I went further and migrated much of setup.py to pyproject.toml.

import pydap
pydap.__version__
>>> version_number

When a new version of pydap is released (say 3.4.2),

% python-c "import pydap; print(pydap.__version__)"
>>> 3.4.2

The versioning is generated during installation. When pydap is installed --editable mode

% pip install -e .
% python -c "import pydap; print(pydap.__version__)"
>>> 0.1.dev680+g61f0c70.d20240321

or so, becoming clear that the developer is using an editable version. This is common practice.