def _check(self, source):
        for nbytes in range(17, 25):
            s = source(nbytes)
            self.assertEquals(len(s), nbytes)
            s2 = source(nbytes)
            self.assertEquals(len(s2), nbytes)
            # This is crude but hey
            self.assertNotEquals(s2, s)
The given random bytes source should return the number of bytes
dataset/ETHPy150Open kuri65536/python-for-android/python-modules/twisted/twisted/test/test_randbytes.py/SecureRandomTestCaseBase._check