Given the task definition and input, reply with output. 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: He continued to work for the Express until 1950 Link Information: Hopkinson became editor of Picture Post, in 1940, remaining until 1950 Question: How long had Tom Hopkinson been editor of the Picture Post for the year Cameron stopped working at the Daily Express?
Answer: 10