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 (isbn VARCHAR, first_edition VARCHAR)
### Question:
What is the ISBN of the book with a first edition in May 2011?
### Answer:
SELECT isbn FROM table_name_42 WHERE first_edition = "may 2011"