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_10 (number VARCHAR, name VARCHAR, builder VARCHAR, date VARCHAR)
### Question:
What number has the builder ruston hornsby, the date 1961, and the name Topsy?
### Answer:
SELECT COUNT(number) FROM table_name_10 WHERE builder = "ruston hornsby" AND date = 1961 AND name = "topsy"