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79:Thing_SetConversation (tid, convid)
- tid: TID of affected thing. If this is 0, the activator is used.
- convid: The number of the conversation associated to the thing. If this is 0, the thing is set not to have any conversation.
Sets the conversation of the thing with the same TID. This can also be used to remove a conversation from a thing, by setting it to 0.