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_81 (seat INTEGER, series_3 VARCHAR)
### Question:
What is the seat number when Series 3 shows Dana Bérová?
### Answer:
SELECT AVG(seat) FROM table_name_81 WHERE series_3 = "dana bérová"