How do I run multiple Python test cases in a loop?

Starting from python 3.4, you can do it like this:

def test_output(self):
    for i in range(1,11):
        with self.subTest(i=i):
            ....
            self.assertEqual(fn(i),output[i])

https://docs.python.org/3.4/library/unittest.html?highlight=subtest#distinguishing-test-iterations-using-subtests