Returns a dictionary with this object's properties merged with all its parent's
        properties.

        The returned dictionary is all the available properties for this object (and their
        associated values).

def _combined_properties(self):
        """Returns a dictionary with this object's properties merged with all its parent's
        properties.

        The returned dictionary is all the available properties for this object (and their
        associated values).
        """
        result = dict(self._properties)
        par = self._parent
        while par:
            result.update(par._properties)
            par = par._parent
        return result