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_34 (callsign VARCHAR, commenced_operations VARCHAR)
### Question:
What callsign has commenced operations in 2011?
### Answer:
SELECT callsign FROM table_name_34 WHERE commenced_operations = 2011