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_25695027_1 (valves VARCHAR, years_built VARCHAR)
### Question:
How many types of valves were used on this engine that was built on 1902-05?
### Answer:
SELECT COUNT(valves) FROM table_25695027_1 WHERE years_built = "1902-05"