Thank you. Hope they could fix it soon.

Time: 474ms Passed: 516 Failed: 0
I passed all the tests but can't submit the solution and didn't get any error information.
Could anyone explain what could be the cause?

Thank you for your information. Now I know the reason. I used numpy, so the dtype in my answer is 'numpy.int64' rather than 'int'. After I converted dtype to int, I pass the test. It seems this issue only occurs for multiple solution sudoku. Why do you check data type for multiple solution sudoku?

I got the following test error message:
✘ You're solution shound only contains int: False should equal True
Could anyone explain what happend? It can be easily checked that the solution is a valid one(if my understanding about this game is right.)
The problem is
[[0, 8, 0, 0, 0, 9, 7, 4, 3], [0, 5, 0, 0, 0, 8, 0, 1, 0], [0, 1, 0, 0, 0, 0, 0, 0, 0], [8, 0, 0, 0, 0, 5, 0, 0, 0], [0, 0, 0, 8, 0, 4, 0, 0, 0], [0, 0, 0, 3, 0, 0, 0, 0, 6], [0, 0, 0, 0, 0, 0, 0, 7, 0], [0, 3, 0, 5, 0, 0, 0, 8, 0], [9, 7, 2, 4, 0, 0, 0, 5, 0]]

The solution I get was:
[[2, 8, 6, 1, 5, 9, 7, 4, 3], [3, 5, 4, 7, 6, 8, 9, 1, 2], [7, 1, 9, 2, 4, 3, 5, 6, 8], [8, 9, 3, 6, 1, 5, 4, 2, 7], [6, 2, 7, 8, 9, 4, 1, 3, 5], [1, 4, 5, 3, 2, 7, 8, 9, 6], [5, 6, 8, 9, 3, 1, 2, 7, 4], [4, 3, 1, 5, 7, 2, 6, 8, 9], [9, 7, 2, 4, 8, 6, 3, 5, 1]]
✘ You're solution shound only contains int: False should equal True

Test Results:
Traceback:
in
AttributeError: 'module' object has no attribute 'expect_equals'.
???

Test Results:
Traceback:
in
AttributeError: 'module' object has no attribute 'expect_equals'

Is the test module not available now??

Traceback:
in
AttributeError: 'module' object has no attribute 'expect_equals'
-------What does this mean??

Traceback:
in
AttributeError: 'module' object has no attribute 'expect_equals'

What does this mean????

I got the same error. And the error message itself is total nonsense and not helpful...

Yes, I think the instructions should be more specific and tell people the format of possible inputs. Is empty array or None or [None] or [None, None] possible input? How to treat None? Ignore it or count it as a placehoder and treat it as 0? I can't figure out what's wrong with my code. I only got very short error message which just caused more confusion rather than being helpful! :(