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_18 (owner_s_ VARCHAR, date VARCHAR, description VARCHAR)
### Question:
Which owner has a description of Mark 1 pos and is dated 1956?
### Answer:
SELECT owner_s_ FROM table_name_18 WHERE date = 1956 AND description = "mark 1 pos"