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: "The Mariinsky Theatre Second Stage hosted which Russo-Austrian soprano on May 2, 2013?" whose answer is Anna Netrebko.
Each document should contain about 30 words, and these documents should contain useful information.

Query: Mariinsky Theatre Second Stage Russo-Austrian soprano May 2, 2013
Useful Output:

Doc 1: Mariinsky Theatre announces inaugural programme for opening of new Mariinsky II opera house in St Petersburg, Russia, 2 – 4 May 2013.
Doc 2: St. Petersburg's long-awaited and newest cultural landmark, the Mariinsky II, is set to open this week.
Doc 3: Mixed reaction in Vienna to Anna Netrebko symbolic of Russian soprano's performing life since Ukraine invasion.
Doc 4: Its four-movement symphonic structure illustrates the cycle of life from childhood memories of sleigh bells, to romantic wedding bells, wild
Doc 5: The opening of the Mariinsky Theatre II, a $700-million venue designed by Toronto architects that is easily among the largest ballet and opera houses in the