Add pickle support to the MSGPackModernSerializer - if a type can't be serialized to native MessagePack, then pickle it

lemoncurry/msgpack.py

@@ -1,11 +1,24 @@
 import msgpack
+import pickle
 
 from django_redis.serializers.base import BaseSerializer
 
 
+def default(obj):
+    # Pickle anything that MessagePack can't handle itself.
+    return msgpack.ExtType(69, pickle.dumps(obj, protocol=4))
+
+
+def ext_hook(code, data):
+    # Unpickle if we pickled - otherwise do nothing.
+    if code == 69:
+        return pickle.loads(data)
+    return msgpack.ExtType(code, data)
+
+
 class MSGPackModernSerializer(BaseSerializer):
     def dumps(self, value):
-        return msgpack.packb(value, use_bin_type=True)
+        return msgpack.packb(value, default=default, use_bin_type=True)
 
     def loads(self, value):
-        return msgpack.unpackb(value, raw=False)
+        return msgpack.unpackb(value, ext_hook=ext_hook, raw=False)