def declarative_relationship(name='Relationship', cls=Edge
                             , metaclass=DeclarativeMeta
                             , **kwargs):
    return declarative_base(DeclarativeType.Edge, name, cls, metaclass
                            , **kwargs)
Create base class for graph relationships/edges
dataset/ETHPy150Open mogui/pyorient/pyorient/ogm/declarative.py/declarative_relationship