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_90 (tonnage VARCHAR, built VARCHAR, ship VARCHAR)
### Question:
The ship SSBergensfjord built before 1973 has what tonnage?
### Answer:
SELECT tonnage FROM table_name_90 WHERE built < 1973 AND ship = "ssbergensfjord"