def METHOD_NAME(self, temp_db_cursor):
    with db_utils.CopyBuffer() as buf:
        buf.add(1, json.dumps({'test': 'value', 'number': 1}))
        buf.copy_out(temp_db_cursor, self.TABLE_NAME)
    assert self.table_rows(temp_db_cursor) == \
               {1: {'test': 'value', 'number': 1}}