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_26 (league VARCHAR, established VARCHAR, club VARCHAR)
### Question:
What is the league established before 1930 with the rayo vallecano club?
### Answer:
SELECT league FROM table_name_26 WHERE established < 1930 AND club = "rayo vallecano"