Is Convex Hull's "Check" broken?

I can't "check" a solution of Convex Hull mission. There is a strange error returned:

/home/site/checkio/runners/py32.py:255: DeprecationWarning: cgi.escape is deprecated, use html.escape instead,
error = u'TypeError: {0} is wrong data type'.format(cgi.escape(str(type(result)))),

I hardcoded the answer of the first test. After adding `assert` before return, the next code passes Test1:

test1_answer = [4, 5, 6, 0, 1, 2, 3]
assert my_ans == test1_answer , 'Err'
return test1_answer

And if I try to return ans, it gives the mentioned error:

test1_answer = [4, 5, 6, 0, 1, 2, 3]
assert my_ans == test1_answer , 'Err'
return my_ans

I can post my code if it's necessary.