Below is an context that describes a sql query, paired with an question that provides further information. Write an answer that appropriately completes the request.  # noqa: E501
### Context:
CREATE TABLE table_name_89 (inversions INTEGER, opened VARCHAR)
### Question:
Name the sum of inversions for opened of april 20, 2002
### Answer:
SELECT SUM(inversions) FROM table_name_89 WHERE opened = "april 20, 2002"