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_27914606_1 (written_by VARCHAR, us_viewers__millions_ VARCHAR)

### Question ###
who were the writers of the episode that had 5.56 millions of north american viewers? 

### Accurate SQL ###

SELECT written_by FROM table_27914606_1 WHERE us_viewers__millions_ = "5.56"