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: "who won the women's 2017 us open?" whose answer is Park Sung-hyun.
Each document should contain about 30 words, and these documents should contain useful information.

Query: 2017 US Open women's singles winner
Useful Output:

Doc 1: Fellow Americans Sloane Stephens and Madison Keys battled it out in the US Open 2017 women's final, with Stephens earning her first career
Doc 2: Stephens defeated five seeds to become the lowest-ranked player to win the US Open since computerized rankings began more than four decades ago.
Doc 3: Watch the extended highlights between Sloane Stephens and Madison Keys in the final of the 2017 US Open  women's singles titles. It was
Doc 4: Sloane Stephens is the women's 2017 U.S. Open champion after a 6-3, 6-0 victory over fellow American Madison Keys in Saturday's final at
Doc 5: Sloane Stephens defeats Madison Keys for US Open women's title – as it happened · Live feed · Stephens breaks in sixth game and wins match!