The plugin or plugin group's top-level folder, and each inner folder that is to be recognized as a package, must be a valid regular package name according to Python's PEP 8 style guide, using only letters, numbers, and underscores.

Each inner folder that is to be recognized as a package must contain a file named __init__.py.

When importing, the full path for the package name must be specified. For example, if a plugin group named ext contains a plugin named demo, which has an inner package named src containing a module named sample, the module must be imported as follows:

from ext.demo.src import sample