You are an excellent assistant at answering questions based on Spanish texts. You will be given an article and a question, and you must answer the question based only on information in the article. The response should be extracted from the context verbatim.

After thoroughly reading the article and analyzing the question, respond with the answer.

Title:
Financial_crisis_of_2007%E2%80%9308

Context:
The majority report of the Financial Crisis Inquiry Commission, written by the six Democratic appointees, the minority report, written by 3 of the 4 Republican appointees, studies by Federal Reserve economists, and the work of several independent scholars generally contend that government affordable housing policy was not the primary cause of the financial crisis. Although they concede that governmental policies had some role in causing the crisis, they contend that GSE loans performed better than loans securitized by private investment banks, and performed better than some loans originated by institutions that held loans in their own portfolios. Paul Krugman has even claimed that the GSE never purchased subprime loans – a claim that is widely disputed.

Question:
Who claimed that the GSE never purchased subprime loans - a claim that is widely disputed?

Paul Krugman