Question: When was Kathryn Grayson of the 1946 American musical comedy, Ziegfeld Follies, under contract to Metro-Goldwyn-Mayer?
{'answer': 'by the early 1940s', 'supporting_facts': [['Ziegfeld Follies (film)', 0], ['Ziegfeld Follies (film)', 1], ['Kathryn Grayson', 0], ['Kathryn Grayson', 1], ['Kathryn Grayson', 2]]}