Orange Canvas Core is a framework for building graphical user interfaces for editing workflows. It is a component used to build the Orange Canvas (http://orange.biolab.si) data-mining application (for which it was developed in the first place).
Orange Canvas Core is pip installable (https://pip.pypa.io/), simply run:
pip install orange-canvas-core
Or use the:
pip install ./
to install from the sources.
Some incomplete documentation is available at https://orange-canvas-core.readthedocs.io