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[prebid-server new adapter PR](https://github.com/prebid/prebid-server/pull/4243)

@bsardo It has been approved for two weeks. May I ask when the branch will be merged?

> Left some comments related to code cleanup. Other than these looks good. @VeronikaSolovei9 I have revised the code according to the suggestions.

@przemkaczmarek I have revised the code according to the suggestions.