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_31 (geohash_length INTEGER, lng_error VARCHAR, lng_bits VARCHAR)
### Question:
What is the highest geohash length when there is a ng error of ±0.00017, and a lng bits smaller than 20?
### Answer:
SELECT MAX(geohash_length) FROM table_name_31 WHERE lng_error = "±0.00017" AND lng_bits < 20