Find the dates of the tests taken with result "Pass".
SELECT date_test_taken FROM Student_Tests_Taken WHERE test_result  =  "Pass"
SELECT date_test_taken FROM Student_Tests_Taken WHERE test_result  =  "Pass"
[{'date_test_taken': '2018-03-25 21:50:22'}, {'date_test_taken': '2018-03-21 00:32:25'}, {'date_test_taken': '2018-03-25 00:44:50'}, {'date_test_taken': '2018-03-25 15:06:12'}, {'date_test_taken': '2018-03-24 13:22:17'}, {'date_test_taken': '2018-03-19 02:04:26'}, {'date_test_taken': '2018-03-23 23:47:42'}, {'date_test_taken': '2018-03-19 14:48:12'}]