Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_28723 ( "No." real, "#" real, "Title" text, "Directed by" text, "Written by" text, "U.S. air date" text, "Production code" text, "U.S. viewers (million)" text )

### Question ###
Who are the writers of the episodes directed by Justin Hartley?

### Accurate SQL ###

SELECT "Written by" FROM table_28723 WHERE "Directed by" = 'Justin Hartley'