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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 _update_expression_reference(self, # pylint: disable=no-self-use grammar: Grammar, parent_expression_nonterminal: str, child_expression_nonterminal: str) -> None: """ When we add a new expression, there may be other expressions that refer to it, and we need to update those to point to the new expression. """

        grammar[parent_expression_nonterminal].members = \
                [member if member.name != child_expression_nonterminal
                 else grammar[child_expression_nonterminal]
                 for member in grammar[parent_expression_nonterminal].members]