As a result, instance is now non-null and refers to a valid Singleton object.

结果是，instance现在为非null并引用一个有效的Singleton对象。

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Workaround: Ensure that you are using valid, non-expired security certificates issued by a trusted root certification authority.

处理：确保您在使用由可信任的根证书颁发机构颁发的有效的、非过期的安全证书。

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Watch for Waste - Millions of tickets go unused, even though most non-refundable fares are valid for travel for up to a year.

虽然多数不可退还的机票的有效期长达一年，但还是有数以百万张机票最后被浪费掉。

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