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_16670746_2 (fastest_lap VARCHAR, winning_team VARCHAR, circuit VARCHAR)

### Question ###
Who had the fastest lap in the race won by Team Impul at the Twin Ring Motegi circuit?

### Accurate SQL ###

SELECT fastest_lap FROM table_16670746_2 WHERE winning_team = "Team Impul" AND circuit = "Twin Ring Motegi"