This unique identifier is required by either your carrier or the third-party unlock provider in order to get your unlock code. To retrieve your IMEI number, follow the appropriate steps for your device:  BlackBerry 10 – Go to Settings, then select Advanced. Tap Hardware from the dropdown menu that appears. Your IMEI number will be listed in the window. BlackBerry 6 and 7 – Click Options, and then click Device. Click Device and Status Information to find the IMEI. BlackBerry 5 and earlier – Click Options and select Status. Your IMEI will be displayed. Your carrier will typically unlock your phone for free after your contract has been fulfilled. This means you will not be able to receive your code unless your contract obligations have been fulfilled and your phone has been completely paid off. If you need to unlock your phone and your carrier will not give you the code, you’ll have to pay for a code from a third-party unlocking service.  Be sure to read reviews for third-party services to make sure that the company you are paying is legitimate. You will need to provide your IMEI number when you request your unlock code. Receiving your code could take up to 3 days, but usually happens within a few hours.

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Write a summary of the previous text in Chinese:
获得IMEI码（国际移动电话设备识别码）。 和运营商联系。 和第三方联系，花钱购买解锁码（如果运营商不提供的话。