def test_repr(self):
self.assertEqual(repr(self.x), "Symbol('x')")
self.assertEqual(repr(self.one), 'Constant(1)')
+ self.assertEqual(repr(self.pi), 'Constant(22, 7)')
self.assertEqual(repr(self.expr), "Expression({'x': 1, 'y': -2}, 3)")
def test_fromstring(self):