diff --git a/snippets/test8.py b/snippets/test8.py
new file mode 100644
index 0000000..3d79d33
--- /dev/null
+++ b/snippets/test8.py
@@ -0,0 +1,64 @@
+import unittest
+import json
+
+class A(object):
+    def __init__(self, arg1=None, arg2=None):
+        self.arg1 = arg1
+        self.arg2 = arg2
+        self.arg3 = self.arg1 + self.arg2
+
+    def __str__(self):
+        return "A: {0!s} {1!s} {2!s}".format(self.arg1, self.arg2, self.arg3)
+
+    def toJSON(self):
+        return json.DUMPS({'type':self.__class__.__name__, 'args': {'arg1':self.arg1, 'arg2':self.arg2}})
+
+
+class Tests(unittest.TestCase):
+    def test_a1(self):
+        a1 = A(1, 2)
+        self.assertEqual(a1.arg1, 1)
+        self.assertEqual(a1.arg2, 2)
+        self.assertEqual(a1.arg3, 3)
+
+    def test_a2(self):
+        a2 = A(**{'arg1':2, 'arg2':4})
+        self.assertEqual(a2.arg1, 2)
+        self.assertEqual(a2.arg2, 4)
+        self.assertEqual(a2.arg3, 6)
+
+    def test_a3(self):
+        j = '{ "type": "A", "args": { "arg1": 3, "arg2": 5 } }'
+        jj = json.loads(j)
+        klass = eval(jj['type'])
+        self.assertEqual(A, klass)
+        a3 = klass(**jj['args'])
+        self.assertEqual(a3.arg1, 3)
+        self.assertEqual(a3.arg2, 5)
+        self.assertEqual(a3.arg3, 8)
+
+    def test_a4(self):
+        j = '{ "type": "A", "args": { "arg1": 3, "arg2": 5 } }'
+        jj = json.loads(j)
+        klass = eval(jj['type'])
+        self.assertEqual(A, klass)
+        a3 = klass(**jj['args'])
+        self.assertEqual(a3.arg1, 3)
+        self.assertEqual(a3.arg2, 5)
+        self.assertEqual(a3.arg3, 8)
+
+        jjjj = json.dumps(a3)
+        print(jjjj)
+        jj = json.loads(jjjj)
+        klass = eval(jj['type'])
+        self.assertEqual(A, klass)
+        a3 = klass(**jj['args'])
+        self.assertEqual(a3.arg1, 3)
+        self.assertEqual(a3.arg2, 5)
+        self.assertEqual(a3.arg3, 8)
+
+
+
+
+if __name__ == '__main__':
+    unittest.main()