user: Question: When did the Mixed double Women's singles of Isabel Rocha, from the year 1970, and a Women's doubles of Isabel Rocha Ana Margarida?
Columns: ['Year', "Men's singles", "Women's singles", "Men's doubles", "Women's doubles", 'Mixed doubles']
Types: ['real', 'text', 'text', 'text', 'text', 'text']
Sample row: [1956.0, 'Jose da Silva', 'Lezita Chaves', 'Jose da Silva Anibal Rebelo', 'no competition', 'Jose da Silva Guida de Freitas']
SQL:

assistant: SELECT "Mixed doubles" FROM "Table" WHERE "Women's singles" = 'Isabel Rocha' AND "Year" > 1970.0 AND "Women's doubles" = 'Isabel Rocha Ana Margarida';