In this task, you're given a statement, further information available on a particular linked term from the statement, and a question. Your job is to generate the answer to the question by using the information provided. If there is no clear answer obtainable, output 'none'.

Context: It is widely believed that Saudi Arabia has been a major financier of Pakistan's own integrated atomic bomb project since 1974, a programme founded by former prime minister Zulfikar Ali Bhutto. Link Information: Zulfikar Ali Bhutto (; ; 5 January 1928 4 April 1979) was a Pakistani barrister and politician who served as the 9th Prime Minister of Pakistan from 1973 to 1977 Question: What years did Zulfikar Ali Bhutto serve as prime minister?
Answer: from 1973 to 1977