human
Considering the provided database schema and associated query, produce SQL code to retrieve the answer to the query. 
###Database Schema: Series #, Season #, Title, Directed by:, Written by:, Original air date
###Question: Who directed the episode that was written by Jackson Gillis and Originally aired on May 21, 1955?
gpt
SELECT Directed by: FROM table WHERE Written by: = Jackson Gillis AND Original air date = May 21, 1955