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_19 (opened INTEGER, manufacturer VARCHAR)
### Question:
Which average Opened has a Manufacturer of vekoma?
### Answer:
SELECT AVG(opened) FROM table_name_19 WHERE manufacturer = "vekoma"