[CGTN] Add new extractor

[chao813]

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• Bug fix
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• New extractor
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[chao813]

@Ashish0804 should this be pending review?

[Ashish0804]

Actually everything else looks fine, I'm just not sure if the timestamp extraction can be handled using an function from utils
I'll mark this as pending-review so someone else knows to take a look at aswell.

[chao813]

@Ashish0804 thanks! The timestamp extraction is working using the unified_timestamp function from utils, its passing the test cases.