def test_diff(self):
n1 = Node()
n2 = Node()
info = Node()
n1['a'] = 1
self.assertTrue(n1.diff(n2, info))
print(info)
n2['a'] = 1
self.assertFalse(n1.diff(n2, info))
n2['b'] = 2.0
self.assertTrue(n1.diff(n2, info))
self.assertFalse(n1.diff_compatible(n2, info))
n1['b'] = 1.0
self.assertFalse(n1.diff(n2, info, 10))
