What does "I'm from Jilin" mean in the joke?

I try to express it in the most common way,

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Students in Taiwan Province Province said:

I'm from China,

There must be nothing wrong with it.

But if you say,

I come from Taiwan Province province,

Then your classmate said,

I'm from Jilin, that is to say,

Taiwan Province Province, like Jilin Province,

Not an independent country

It is only a province of China.

Your classmate is very patriotic,

I hope lz you can understand what I mean-