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In this task, you're given an article and an answer. Your task is to generate the question for the answer based on the given article.

Article: There are a lot of public libraries in Britain. These libraries have more than one hundred and fifteen million books, not including those libraries of public schools. Public libraries not only lend books, music records but also help children, patients in hospitals and others to get special play readings, film shows and so on. The first public libraries were founded in about the year 1850. Today's public libraries usually have a reading-room, a lending room and a reference room. The greatest and most famous library in Britain is that of the British Library in London. It was founded in 1973 and has over 10, 000, 000 books. It has nearly every magazine, newspaper and book published in Britain and other parts across the world. 
 Answer: 10,000,000 or less.
Solution: How many books are there in the British Library?
Why? In the Article, 10,000,000 is mentioned for the number of books available in the British Library, so this is a good question.

New input: Article: Most of the news in the newspapers is bad but sometimes there is a story with good news. This is one of those stories. Millions of people around the world suffer from AIDS, malaria, tuberculosis, and other serious diseases. There are medicines to treat these diseases but for people in poor countries, these medicines are too expensive to buy. When a pharmaceutical company produces a new medicine, they receive a special license called a _ This license means that the new medicine or drug is protected for a period of 20 years. The company that produced the drug can fix the price of the drug and no other company is allowed to produce the same drug or a copy of the drug for 20 years. At the moment, these patents operate all over the world, both in rich countries and in poor countries. The drugs companies say that they need patents so that they can get the money to pay for research to find new drugs and medicines. In rich countries people usually have enough money to pay for these drugs but in poor countries people can't afford to buy them and cannot treat diseases like AIDS and malaria. Last month, however, a group of experts published a report which says that patents are very bad for poor countries. The report says that drug companies do not want to find new medicines for diseases of poor people in poor countries. It says that poor countries should be allowed to buy cheap drugs without patents from other countries.     The authors of the report were lawyers, scientists and a senior director from the drug company Pfizer. Of course, the pharmaceuticals industry doesn't agree with the report, "We need patents so that we can develop new medicines to fight disease both in the developed and developing world," said a spokesman. But the report is the first sign that there might be a change in the patent system. This change could save millions of lives in the world's poorest countries. This really is good news. 
 Answer: They are protected by patents.
Solution:
Why are medicines expensive for people in poor countries?