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来源：雅诚德英语网
Next, you need to create your Extension class, as shown in listing 5, which includes.
接下来，需要创建extension类，如清单5所示，包括以下内容。
Next, you need to create your Extension class, as shown in listing 5, which includes.
接下来，需要创建extension类，如清单5所示，包括以下内容。