Definition: In this task, you need to generate an appropriate title for the given summary of some paragraph. The generated title must be short and should include the main topic of the given text. Your summary should be less than 20 words long.
Input: North Korea says it has carried out its first test of a hydrogen bomb with "perfect success". John Nilsson-Wright, head of the Asia Programme at Chatham House, examines how plausible the claim is, and what it could mean for the region.

North Korea nuclear: What now after H-bomb test claim?