diff --git a/client/openapi_server/__init__.py b/client/openapi_server/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/client/openapi_server/encoder.py b/client/openapi_server/encoder.py
new file mode 100644
index 0000000..8682003
--- /dev/null
+++ b/client/openapi_server/encoder.py
@@ -0,0 +1,19 @@
+from json import JSONEncoder
+
+from openapi_server.models.base_model import Model
+
+
+class JSONEncoder(JSONEncoder):
+    include_nulls = False
+
+    def default(self, o):
+        if isinstance(o, Model):
+            dikt = {}
+            for attr in o.openapi_types:
+                value = getattr(o, attr)
+                if value is None and not self.include_nulls:
+                    continue
+                attr = o.attribute_map[attr]
+                dikt[attr] = value
+            return dikt
+        return JSONEncoder.default(self, o)
diff --git a/client/openapi_server/typing_utils.py b/client/openapi_server/typing_utils.py
new file mode 100644
index 0000000..74e3c91
--- /dev/null
+++ b/client/openapi_server/typing_utils.py
@@ -0,0 +1,30 @@
+import sys
+
+if sys.version_info < (3, 7):
+    import typing
+
+    def is_generic(klass):
+        """ Determine whether klass is a generic class """
+        return type(klass) == typing.GenericMeta
+
+    def is_dict(klass):
+        """ Determine whether klass is a Dict """
+        return klass.__extra__ == dict
+
+    def is_list(klass):
+        """ Determine whether klass is a List """
+        return klass.__extra__ == list
+
+else:
+
+    def is_generic(klass):
+        """ Determine whether klass is a generic class """
+        return hasattr(klass, '__origin__')
+
+    def is_dict(klass):
+        """ Determine whether klass is a Dict """
+        return klass.__origin__ == dict
+
+    def is_list(klass):
+        """ Determine whether klass is a List """
+        return klass.__origin__ == list