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Is every group an ideal class group of a number field?

The inverse Galois problem asks whether every finite group appears as the Galois group of some finite extension of $\mathbb Q$. I was wondering to what extent the analogous problem for ideal class groups has been investigated. More precisely, consider the following question:

Is every finite abelian group the ideal class group of some number field (finite extension of $\mathbb Q$)?

I'd be interested to hear about any partial results, as I suppose this question is still open. I'd be also interested in any results about a weaker problem:

Is every positive integer the ideal class number of some number field?

Again, any reference, even to a partial result, will be appreciated.