I am building my first ever python package, currently I have this structure:

my_project_root_dir/
└--package_name/
   └--networking/
      |--__init__.py
      └--service_discovery.py
   |--__init__.py
   └--adapter.py
|--README.md
└--setup.py

Then in adapter.py i have import statement:

from package_name.networking.service_discovery import ServiceDiscovery

In package_name.__init__.py:

__all__ = ['networking']

In networking.__init__py:

__all__ = ['service_discovery']

In networking.service_discovery.py there is class definition of ServiceDiscovery

And then when I try to install locally this package into different virtual environment through: pip install /path-to-project-dir/my_project_root_dir

And run in python console import package_name.adapter I get the error:

ModuleNotFoundError: No module named 'package_name.networking'

with the traceback to adapter.py file