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_225098_4 (date_successor_seated VARCHAR, district VARCHAR)
### Question:
The successor for the Massachusetts 20th district was seated on what date?
### Answer:
SELECT date_successor_seated FROM table_225098_4 WHERE district = "Massachusetts 20th"