Utility function mimicking the behavior of the old SA synonym function
    with the new hybrid property semantics.

def synonym(name):
    """
    Utility function mimicking the behavior of the old SA synonym function
    with the new hybrid property semantics.
    """
    return hybrid_property(lambda inst: getattr(inst, name),
                           lambda inst, value: setattr(inst, name, value),
                           expr=lambda cls: getattr(cls, name))