Fixed hashing of EmbeddedDocuments (#348)

tests/document/instance.py

@@ -1705,6 +1705,14 @@ class InstanceTest(unittest.TestCase):
 
         self.assertTrue(u1 in all_user_set)
 
+    def test_embedded_document_hash(self):
+        """Test embedded document can be hashed
+        """
+        class User(EmbeddedDocument):
+            pass
+
+        hash(User())
+
     def test_picklable(self):
 
         pickle_doc = PickleTest(number=1, string="One", lists=['1', '2'])