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 performed the first open heart surgery in america?" whose answer is Daniel Hale Williams.
Each document should contain about 30 words, and these documents should contain useful information.

Query: first open heart surgery performed in america
Useful Output:

Doc 1: On May 6th, 2003, we celebrate the 50th anniversary of the first successful open-heart operation performed with the use of the heart-lung machine,
Doc 2: Daniel Hale Williams performed the first successful open heart surgery during an emergency procedure. The African American doctor had to think on his toes
Doc 3: Dr. John Gibbon invented the heart-lung machine and used it to perform the world's first successful open-heart surgery on May 6, 1953.
Doc 4: Believe it or not, but one of the world's first open heart surgery's happened right here in Chicago! In 1891, the Provident Hospital and
Doc 5: Heart valve replacement in adults wasn't successful until 1960 when the US surgeon Albert Starr implanted a mechanical valve that he had in fact