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_42 (took_office INTEGER, left_office VARCHAR)
### Question:
What is the Took Office Date of the Presidency that Left Office Incumbent?
### Answer:
SELECT SUM(took_office) FROM table_name_42 WHERE left_office = "incumbent"