Meaning of 'That seems to be it' in context

Read the passage and answer the question below

John: Have you ever done any of these extramural courses before?
Amy: No don't think so although I did do something on psychodrama once but no it wasn't extramural was it?
John: That seems to be it.

Question: Previous extramural courses attended by Amy:_____

I put psychodrama there as I thought John said that psychodrama seems to be a extramural course, but the answer says it should be 'no'. I am always confused with tag questions and do not understand what 'That seems to be it' means.

Solution 1:

In this case, I would consider "That seems to be it" as an affirmation of the fact that psychodrama is not an extramural course. If you consider "That seems to be it" to be analogous to "That seems to be the case", it clears things up quite a bit.

As an example,
Mr Jones had had the card all along.
That seems to be the case.

Solution 2:

Since Amy has already said, in effect, No, the phrase “That seems to be it” is an interview ender, and means that all the questions have been asked.

Given that this is ambiguous, that choice is likely, as “That seems to be it” or some variant of it is frequently used this way.

John and Amy seem to agree that psychodrama is not extramural.