Given a namespace preorder hash, determine if it is preordered
        at the current block.

def is_namespace_preordered( self, namespace_id_hash ):
        """
        Given a namespace preorder hash, determine if it is preordered
        at the current block.
        """
        namespace_preorder = self.get_namespace_preorder(namespace_id_hash)
        if namespace_preorder is None:
            return False 
        else:
            return True