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 Project_Staff (role_code VARCHAR, date_from VARCHAR, date_to VARCHAR)
### Question:
What are the staff roles of the staff who
### Answer:
SELECT role_code FROM Project_Staff WHERE date_from > '2003-04-19 15:06:20' AND date_to < '2016-03-15 00:33:18'