Below is an context that describes a sql query, paired with an question that provides further information. Write an answer that appropriately completes the request.  # noqa: E501
### Context:
CREATE TABLE table_name_45 (level INTEGER, leaguecontested VARCHAR, season VARCHAR)
### Question:
Which Level has a League Contested of northern premier league premier division, and a Season of 2011–12?
### Answer:
SELECT AVG(level) FROM table_name_45 WHERE leaguecontested = "northern premier league premier division" AND season = "2011–12"