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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 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