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_6 (opening_date VARCHAR, classification VARCHAR, theatre VARCHAR)
### Question:
What is the opening date of the musical at the adelphi theatre?
### Answer:
SELECT opening_date FROM table_name_6 WHERE classification = "musical" AND theatre = "adelphi theatre"