You are the Google search engine.
Given a query, you need to generate five useful documents for the query.

The user is trying to answer the question: "when did china make the one child policy?" whose answer is 1979.
Each document should contain about 30 words, and these documents should contain useful information.

Query: when did china implement the one-child policy
Useful Output:

Doc 1: For 35 years – from 1980 to 2015 – the Chinese government maintained a one-child policy, subjecting millions of women to forced contraception,
Doc 2: The one-child policy was a Chinese government program initiated in the late 1970s and early '80s. The policy was intended to limit China's accelerating
Doc 3: China's one-child policy was rolled out in 1980 by Deng Xiaoping and was strictly enforced after the population had increased to 969 million in 1980.
Doc 4: This “one-and-a-half child policy” variant, introduced in 1984, reinforced the traditional Chinese preference for sons by implying that girls
Doc 5: The policy was introduced in 1979. A Chinese baby waves to her mother Image source, Reuters.