Who wrote the episode that has a production code 3x7557?
CREATE TABLE table_22347090_6 (written_by VARCHAR, production_code VARCHAR)
SELECT written_by FROM table_22347090_6 WHERE production_code = "3X7557"
<s>[INST] Write mssql query to answer the following question given the database schema. Schema: CREATE TABLE table_22347090_6 (written_by VARCHAR, production_code VARCHAR) Question: Who wrote the episode that has a production code 3x7557? [/INST] SELECT written_by FROM table_22347090_6 WHERE production_code = "3X7557" </s>