diff --git a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/PythonClientExperimentalCodegen.java b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/PythonClientExperimentalCodegen.java
index eb3c65438ea9..428d6f7635f5 100644
--- a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/PythonClientExperimentalCodegen.java
+++ b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/PythonClientExperimentalCodegen.java
@@ -651,7 +651,7 @@ public void postProcessParameter(CodegenParameter p) {
         // set baseType to null so the api docs will not point to a model for languageSpecificPrimitives
         if (p.baseType != null && languageSpecificPrimitives.contains(p.baseType)){
             p.baseType = null;
-        } else if (p.isListContainer && p.mostInnerItems.complexType != null && !languageSpecificPrimitives.contains(p.mostInnerItems.complexType)) {
+        } else if (p.isListContainer && p.mostInnerItems != null && p.mostInnerItems.complexType != null && !languageSpecificPrimitives.contains(p.mostInnerItems.complexType)) {
             // fix ListContainers
             p.baseType = getPythonClassName(p.mostInnerItems.complexType);
         }
diff --git a/modules/openapi-generator/src/main/resources/python/python-experimental/model_templates/classvars.mustache b/modules/openapi-generator/src/main/resources/python/python-experimental/model_templates/classvars.mustache
index fcd8a71fd124..3e607fa552e1 100644
--- a/modules/openapi-generator/src/main/resources/python/python-experimental/model_templates/classvars.mustache
+++ b/modules/openapi-generator/src/main/resources/python/python-experimental/model_templates/classvars.mustache
@@ -29,7 +29,10 @@
 {{/optionalVars}}
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
 {{#requiredVars}}
         '{{name}}': ({{{dataType}}},),  # noqa: E501
 {{/requiredVars}}
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/additional_properties_any_type.py b/samples/client/petstore/python-experimental/petstore_api/models/additional_properties_any_type.py
index e3bdd37fcc98..29898242a429 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/additional_properties_any_type.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/additional_properties_any_type.py
@@ -59,7 +59,10 @@ class AdditionalPropertiesAnyType(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'name': (str,),  # noqa: E501
     }
 
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/additional_properties_array.py b/samples/client/petstore/python-experimental/petstore_api/models/additional_properties_array.py
index 12f228e9ba9d..87b4e02d99ce 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/additional_properties_array.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/additional_properties_array.py
@@ -59,7 +59,10 @@ class AdditionalPropertiesArray(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'name': (str,),  # noqa: E501
     }
 
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/additional_properties_boolean.py b/samples/client/petstore/python-experimental/petstore_api/models/additional_properties_boolean.py
index ed37ef90c4f6..5a5011368eb1 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/additional_properties_boolean.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/additional_properties_boolean.py
@@ -59,7 +59,10 @@ class AdditionalPropertiesBoolean(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'name': (str,),  # noqa: E501
     }
 
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/additional_properties_class.py b/samples/client/petstore/python-experimental/petstore_api/models/additional_properties_class.py
index 3f34d95684b1..e026e045f29b 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/additional_properties_class.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/additional_properties_class.py
@@ -59,7 +59,10 @@ class AdditionalPropertiesClass(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'map_string': ({str: (str,)},),  # noqa: E501
         'map_number': ({str: (float,)},),  # noqa: E501
         'map_integer': ({str: (int,)},),  # noqa: E501
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/additional_properties_integer.py b/samples/client/petstore/python-experimental/petstore_api/models/additional_properties_integer.py
index 653350f6b55d..23d36f751b2d 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/additional_properties_integer.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/additional_properties_integer.py
@@ -59,7 +59,10 @@ class AdditionalPropertiesInteger(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'name': (str,),  # noqa: E501
     }
 
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/additional_properties_number.py b/samples/client/petstore/python-experimental/petstore_api/models/additional_properties_number.py
index e6d75b406361..2a801fdadfbf 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/additional_properties_number.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/additional_properties_number.py
@@ -59,7 +59,10 @@ class AdditionalPropertiesNumber(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'name': (str,),  # noqa: E501
     }
 
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/additional_properties_object.py b/samples/client/petstore/python-experimental/petstore_api/models/additional_properties_object.py
index a3cb690eb769..09a12a1a3eef 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/additional_properties_object.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/additional_properties_object.py
@@ -59,7 +59,10 @@ class AdditionalPropertiesObject(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'name': (str,),  # noqa: E501
     }
 
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/additional_properties_string.py b/samples/client/petstore/python-experimental/petstore_api/models/additional_properties_string.py
index 1611d7c64081..bf94cfad6ff2 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/additional_properties_string.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/additional_properties_string.py
@@ -59,7 +59,10 @@ class AdditionalPropertiesString(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'name': (str,),  # noqa: E501
     }
 
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/animal.py b/samples/client/petstore/python-experimental/petstore_api/models/animal.py
index 106bf5e7649e..5af2aaae7997 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/animal.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/animal.py
@@ -67,7 +67,10 @@ class Animal(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'class_name': (str,),  # noqa: E501
         'color': (str,),  # noqa: E501
     }
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/api_response.py b/samples/client/petstore/python-experimental/petstore_api/models/api_response.py
index e7516d6c7590..6d297ee1fea2 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/api_response.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/api_response.py
@@ -59,7 +59,10 @@ class ApiResponse(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'code': (int,),  # noqa: E501
         'type': (str,),  # noqa: E501
         'message': (str,),  # noqa: E501
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/array_of_array_of_number_only.py b/samples/client/petstore/python-experimental/petstore_api/models/array_of_array_of_number_only.py
index 76165622532e..8aa05bbca301 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/array_of_array_of_number_only.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/array_of_array_of_number_only.py
@@ -59,7 +59,10 @@ class ArrayOfArrayOfNumberOnly(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'array_array_number': ([[float]],),  # noqa: E501
     }
 
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/array_of_number_only.py b/samples/client/petstore/python-experimental/petstore_api/models/array_of_number_only.py
index 165e0eed8192..510c0aaf586a 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/array_of_number_only.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/array_of_number_only.py
@@ -59,7 +59,10 @@ class ArrayOfNumberOnly(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'array_number': ([float],),  # noqa: E501
     }
 
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/array_test.py b/samples/client/petstore/python-experimental/petstore_api/models/array_test.py
index 72418960f571..238f86979aca 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/array_test.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/array_test.py
@@ -63,7 +63,10 @@ class ArrayTest(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'array_of_string': ([str],),  # noqa: E501
         'array_array_of_integer': ([[int]],),  # noqa: E501
         'array_array_of_model': ([[read_only_first.ReadOnlyFirst]],),  # noqa: E501
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/capitalization.py b/samples/client/petstore/python-experimental/petstore_api/models/capitalization.py
index a25472b19da3..df9c54bb2959 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/capitalization.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/capitalization.py
@@ -59,7 +59,10 @@ class Capitalization(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'small_camel': (str,),  # noqa: E501
         'capital_camel': (str,),  # noqa: E501
         'small_snake': (str,),  # noqa: E501
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/cat.py b/samples/client/petstore/python-experimental/petstore_api/models/cat.py
index fc9ab76fbfda..9207afbe8221 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/cat.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/cat.py
@@ -67,7 +67,10 @@ class Cat(ModelComposed):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'class_name': (str,),  # noqa: E501
         'declawed': (bool,),  # noqa: E501
         'color': (str,),  # noqa: E501
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/cat_all_of.py b/samples/client/petstore/python-experimental/petstore_api/models/cat_all_of.py
index 4e4c87e90d42..e7594eaf16c6 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/cat_all_of.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/cat_all_of.py
@@ -59,7 +59,10 @@ class CatAllOf(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'declawed': (bool,),  # noqa: E501
     }
 
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/category.py b/samples/client/petstore/python-experimental/petstore_api/models/category.py
index 08c3e8aad969..5f44fade6531 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/category.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/category.py
@@ -59,7 +59,10 @@ class Category(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'name': (str,),  # noqa: E501
         'id': (int,),  # noqa: E501
     }
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/child.py b/samples/client/petstore/python-experimental/petstore_api/models/child.py
index 7e5e332f0088..7ca6d47b8fbc 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/child.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/child.py
@@ -67,7 +67,10 @@ class Child(ModelComposed):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'radio_waves': (bool,),  # noqa: E501
         'tele_vision': (bool,),  # noqa: E501
         'inter_net': (bool,),  # noqa: E501
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/child_all_of.py b/samples/client/petstore/python-experimental/petstore_api/models/child_all_of.py
index 3cb28139b174..2afe7d0cb4aa 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/child_all_of.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/child_all_of.py
@@ -59,7 +59,10 @@ class ChildAllOf(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'inter_net': (bool,),  # noqa: E501
     }
 
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/child_cat.py b/samples/client/petstore/python-experimental/petstore_api/models/child_cat.py
index 58c0318faf0f..1db1b23ee7f1 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/child_cat.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/child_cat.py
@@ -67,7 +67,10 @@ class ChildCat(ModelComposed):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'pet_type': (str,),  # noqa: E501
         'name': (str,),  # noqa: E501
     }
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/child_cat_all_of.py b/samples/client/petstore/python-experimental/petstore_api/models/child_cat_all_of.py
index de70d839cf28..572a13ab949f 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/child_cat_all_of.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/child_cat_all_of.py
@@ -59,7 +59,10 @@ class ChildCatAllOf(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'name': (str,),  # noqa: E501
     }
 
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/child_dog.py b/samples/client/petstore/python-experimental/petstore_api/models/child_dog.py
index 450e6983fca5..d0ec906b57d4 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/child_dog.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/child_dog.py
@@ -67,7 +67,10 @@ class ChildDog(ModelComposed):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'pet_type': (str,),  # noqa: E501
         'bark': (str,),  # noqa: E501
     }
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/child_dog_all_of.py b/samples/client/petstore/python-experimental/petstore_api/models/child_dog_all_of.py
index 37d900f2c2be..93fc470af14b 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/child_dog_all_of.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/child_dog_all_of.py
@@ -59,7 +59,10 @@ class ChildDogAllOf(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'bark': (str,),  # noqa: E501
     }
 
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/child_lizard.py b/samples/client/petstore/python-experimental/petstore_api/models/child_lizard.py
index 169d05b51364..06d696d863c2 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/child_lizard.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/child_lizard.py
@@ -67,7 +67,10 @@ class ChildLizard(ModelComposed):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'pet_type': (str,),  # noqa: E501
         'loves_rocks': (bool,),  # noqa: E501
     }
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/child_lizard_all_of.py b/samples/client/petstore/python-experimental/petstore_api/models/child_lizard_all_of.py
index 6b6f8d99279d..f3474047aa57 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/child_lizard_all_of.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/child_lizard_all_of.py
@@ -59,7 +59,10 @@ class ChildLizardAllOf(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'loves_rocks': (bool,),  # noqa: E501
     }
 
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/class_model.py b/samples/client/petstore/python-experimental/petstore_api/models/class_model.py
index 4f6fd3bca5e5..96fbad25a1b3 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/class_model.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/class_model.py
@@ -59,7 +59,10 @@ class ClassModel(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         '_class': (str,),  # noqa: E501
     }
 
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/client.py b/samples/client/petstore/python-experimental/petstore_api/models/client.py
index 398d1b7ce0d6..81c0a8de8f28 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/client.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/client.py
@@ -59,7 +59,10 @@ class Client(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'client': (str,),  # noqa: E501
     }
 
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/dog.py b/samples/client/petstore/python-experimental/petstore_api/models/dog.py
index f27e858b4c14..6181904c9dc4 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/dog.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/dog.py
@@ -67,7 +67,10 @@ class Dog(ModelComposed):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'class_name': (str,),  # noqa: E501
         'breed': (str,),  # noqa: E501
         'color': (str,),  # noqa: E501
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/dog_all_of.py b/samples/client/petstore/python-experimental/petstore_api/models/dog_all_of.py
index 18e9270a4c6b..f1ec95341065 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/dog_all_of.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/dog_all_of.py
@@ -59,7 +59,10 @@ class DogAllOf(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'breed': (str,),  # noqa: E501
     }
 
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/enum_arrays.py b/samples/client/petstore/python-experimental/petstore_api/models/enum_arrays.py
index 167f573d4521..b8a77aa5a4fd 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/enum_arrays.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/enum_arrays.py
@@ -67,7 +67,10 @@ class EnumArrays(ModelNormal):
         },
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'just_symbol': (str,),  # noqa: E501
         'array_enum': ([str],),  # noqa: E501
     }
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/enum_class.py b/samples/client/petstore/python-experimental/petstore_api/models/enum_class.py
index b80116abce16..85dab346f0e1 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/enum_class.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/enum_class.py
@@ -60,7 +60,10 @@ class EnumClass(ModelSimple):
         },
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'value': (str,),  # noqa: E501
     }
 
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/enum_test.py b/samples/client/petstore/python-experimental/petstore_api/models/enum_test.py
index c7bef7cc3200..e2f198b5ad14 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/enum_test.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/enum_test.py
@@ -81,7 +81,10 @@ class EnumTest(ModelNormal):
         },
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'enum_string_required': (str,),  # noqa: E501
         'enum_string': (str,),  # noqa: E501
         'enum_integer': (int,),  # noqa: E501
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/file.py b/samples/client/petstore/python-experimental/petstore_api/models/file.py
index eb71f20abb36..0706236722a4 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/file.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/file.py
@@ -59,7 +59,10 @@ class File(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'source_uri': (str,),  # noqa: E501
     }
 
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/file_schema_test_class.py b/samples/client/petstore/python-experimental/petstore_api/models/file_schema_test_class.py
index b612ecf317c8..729005407e6c 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/file_schema_test_class.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/file_schema_test_class.py
@@ -63,7 +63,10 @@ class FileSchemaTestClass(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'file': (file.File,),  # noqa: E501
         'files': ([file.File],),  # noqa: E501
     }
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/format_test.py b/samples/client/petstore/python-experimental/petstore_api/models/format_test.py
index 7b455ece510c..b71adcb3bf7e 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/format_test.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/format_test.py
@@ -59,7 +59,10 @@ class FormatTest(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'number': (float,),  # noqa: E501
         'byte': (str,),  # noqa: E501
         'date': (date,),  # noqa: E501
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/grandparent.py b/samples/client/petstore/python-experimental/petstore_api/models/grandparent.py
index 26bae108ad1e..d55cff43443f 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/grandparent.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/grandparent.py
@@ -59,7 +59,10 @@ class Grandparent(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'radio_waves': (bool,),  # noqa: E501
     }
 
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/grandparent_animal.py b/samples/client/petstore/python-experimental/petstore_api/models/grandparent_animal.py
index 5d99b80c162c..c201995c239a 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/grandparent_animal.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/grandparent_animal.py
@@ -59,7 +59,10 @@ class GrandparentAnimal(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'pet_type': (str,),  # noqa: E501
     }
 
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/has_only_read_only.py b/samples/client/petstore/python-experimental/petstore_api/models/has_only_read_only.py
index 593a6280d3db..1172e9d5df92 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/has_only_read_only.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/has_only_read_only.py
@@ -59,7 +59,10 @@ class HasOnlyReadOnly(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'bar': (str,),  # noqa: E501
         'foo': (str,),  # noqa: E501
     }
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/list.py b/samples/client/petstore/python-experimental/petstore_api/models/list.py
index 362ac90e2c92..f7c7544968cb 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/list.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/list.py
@@ -59,7 +59,10 @@ class List(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         '_123_list': (str,),  # noqa: E501
     }
 
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/map_test.py b/samples/client/petstore/python-experimental/petstore_api/models/map_test.py
index 475332634ab2..d631d92a0896 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/map_test.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/map_test.py
@@ -67,7 +67,10 @@ class MapTest(ModelNormal):
         },
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'map_map_of_string': ({str: ({str: (str,)},)},),  # noqa: E501
         'map_of_enum_string': ({str: (str,)},),  # noqa: E501
         'direct_map': ({str: (bool,)},),  # noqa: E501
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/mixed_properties_and_additional_properties_class.py b/samples/client/petstore/python-experimental/petstore_api/models/mixed_properties_and_additional_properties_class.py
index a88a56b5cf55..3baeb21810a2 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/mixed_properties_and_additional_properties_class.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/mixed_properties_and_additional_properties_class.py
@@ -63,7 +63,10 @@ class MixedPropertiesAndAdditionalPropertiesClass(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'uuid': (str,),  # noqa: E501
         'date_time': (datetime,),  # noqa: E501
         'map': ({str: (animal.Animal,)},),  # noqa: E501
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/model200_response.py b/samples/client/petstore/python-experimental/petstore_api/models/model200_response.py
index 1fabb5e9b50a..349b8c77b1aa 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/model200_response.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/model200_response.py
@@ -59,7 +59,10 @@ class Model200Response(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'name': (int,),  # noqa: E501
         '_class': (str,),  # noqa: E501
     }
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/model_return.py b/samples/client/petstore/python-experimental/petstore_api/models/model_return.py
index 3466f9d2e691..1d00b2f71ee4 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/model_return.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/model_return.py
@@ -59,7 +59,10 @@ class ModelReturn(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         '_return': (int,),  # noqa: E501
     }
 
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/name.py b/samples/client/petstore/python-experimental/petstore_api/models/name.py
index 39f9a4719daf..596a02cd66b0 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/name.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/name.py
@@ -59,7 +59,10 @@ class Name(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'name': (int,),  # noqa: E501
         'snake_case': (int,),  # noqa: E501
         '_property': (str,),  # noqa: E501
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/number_only.py b/samples/client/petstore/python-experimental/petstore_api/models/number_only.py
index 96c03cef11dc..8d2773bb6f77 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/number_only.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/number_only.py
@@ -59,7 +59,10 @@ class NumberOnly(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'just_number': (float,),  # noqa: E501
     }
 
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/order.py b/samples/client/petstore/python-experimental/petstore_api/models/order.py
index ad4e10f0b042..9f5b22f6b960 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/order.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/order.py
@@ -64,7 +64,10 @@ class Order(ModelNormal):
         },
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'id': (int,),  # noqa: E501
         'pet_id': (int,),  # noqa: E501
         'quantity': (int,),  # noqa: E501
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/outer_composite.py b/samples/client/petstore/python-experimental/petstore_api/models/outer_composite.py
index 6ad00966eae6..883d61a1d143 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/outer_composite.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/outer_composite.py
@@ -63,7 +63,10 @@ class OuterComposite(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'my_number': (outer_number.OuterNumber,),  # noqa: E501
         'my_string': (str,),  # noqa: E501
         'my_boolean': (bool,),  # noqa: E501
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/outer_enum.py b/samples/client/petstore/python-experimental/petstore_api/models/outer_enum.py
index 39b104f64271..1c3c266520cb 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/outer_enum.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/outer_enum.py
@@ -60,7 +60,10 @@ class OuterEnum(ModelSimple):
         },
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'value': (str,),  # noqa: E501
     }
 
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/outer_number.py b/samples/client/petstore/python-experimental/petstore_api/models/outer_number.py
index 362a3cf1fc51..57e7d944e678 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/outer_number.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/outer_number.py
@@ -55,7 +55,10 @@ class OuterNumber(ModelSimple):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'value': (float,),  # noqa: E501
     }
 
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/parent.py b/samples/client/petstore/python-experimental/petstore_api/models/parent.py
index d07ca49d4de1..c91a32567b8f 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/parent.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/parent.py
@@ -67,7 +67,10 @@ class Parent(ModelComposed):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'radio_waves': (bool,),  # noqa: E501
         'tele_vision': (bool,),  # noqa: E501
     }
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/parent_all_of.py b/samples/client/petstore/python-experimental/petstore_api/models/parent_all_of.py
index 0cfcbda855d5..135b4c1c642a 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/parent_all_of.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/parent_all_of.py
@@ -59,7 +59,10 @@ class ParentAllOf(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'tele_vision': (bool,),  # noqa: E501
     }
 
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/parent_pet.py b/samples/client/petstore/python-experimental/petstore_api/models/parent_pet.py
index 59b890e89142..2e263aff2ede 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/parent_pet.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/parent_pet.py
@@ -75,7 +75,10 @@ class ParentPet(ModelComposed):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'pet_type': (str,),  # noqa: E501
     }
 
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/pet.py b/samples/client/petstore/python-experimental/petstore_api/models/pet.py
index 081be0210e60..770330f0e9ac 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/pet.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/pet.py
@@ -72,7 +72,10 @@ class Pet(ModelNormal):
         },
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'name': (str,),  # noqa: E501
         'photo_urls': ([str],),  # noqa: E501
         'id': (int,),  # noqa: E501
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/read_only_first.py b/samples/client/petstore/python-experimental/petstore_api/models/read_only_first.py
index 71ca20529129..2a9b97fd2d83 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/read_only_first.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/read_only_first.py
@@ -59,7 +59,10 @@ class ReadOnlyFirst(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'bar': (str,),  # noqa: E501
         'baz': (str,),  # noqa: E501
     }
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/special_model_name.py b/samples/client/petstore/python-experimental/petstore_api/models/special_model_name.py
index 574c3817d786..bc877d3c4e31 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/special_model_name.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/special_model_name.py
@@ -59,7 +59,10 @@ class SpecialModelName(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'special_property_name': (int,),  # noqa: E501
     }
 
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/string_boolean_map.py b/samples/client/petstore/python-experimental/petstore_api/models/string_boolean_map.py
index 19b3cd131c08..929593ed3802 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/string_boolean_map.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/string_boolean_map.py
@@ -59,7 +59,10 @@ class StringBooleanMap(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
     }
 
     validations = {
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/tag.py b/samples/client/petstore/python-experimental/petstore_api/models/tag.py
index 590b234d4d42..ba28d362e578 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/tag.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/tag.py
@@ -59,7 +59,10 @@ class Tag(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'id': (int,),  # noqa: E501
         'name': (str,),  # noqa: E501
         'full_name': (str,),  # noqa: E501
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/type_holder_default.py b/samples/client/petstore/python-experimental/petstore_api/models/type_holder_default.py
index 71b4719f5dd0..799e2d497151 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/type_holder_default.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/type_holder_default.py
@@ -59,7 +59,10 @@ class TypeHolderDefault(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'string_item': (str,),  # noqa: E501
         'number_item': (float,),  # noqa: E501
         'integer_item': (int,),  # noqa: E501
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/type_holder_example.py b/samples/client/petstore/python-experimental/petstore_api/models/type_holder_example.py
index 96b8551dd1a5..4f147b686690 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/type_holder_example.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/type_holder_example.py
@@ -68,7 +68,10 @@ class TypeHolderExample(ModelNormal):
         },
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'string_item': (str,),  # noqa: E501
         'number_item': (float,),  # noqa: E501
         'integer_item': (int,),  # noqa: E501
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/user.py b/samples/client/petstore/python-experimental/petstore_api/models/user.py
index 03b3ef6a5e69..4493c33caf2c 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/user.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/user.py
@@ -59,7 +59,10 @@ class User(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'id': (int,),  # noqa: E501
         'username': (str,),  # noqa: E501
         'first_name': (str,),  # noqa: E501
diff --git a/samples/client/petstore/python-experimental/petstore_api/models/xml_item.py b/samples/client/petstore/python-experimental/petstore_api/models/xml_item.py
index a38afa9cfbec..2e00b0739041 100644
--- a/samples/client/petstore/python-experimental/petstore_api/models/xml_item.py
+++ b/samples/client/petstore/python-experimental/petstore_api/models/xml_item.py
@@ -59,7 +59,10 @@ class XmlItem(ModelNormal):
     allowed_values = {
     }
 
-    openapi_types = {
+    @staticmethod
+    @property
+    def openapi_types():
+        return {
         'attribute_string': (str,),  # noqa: E501
         'attribute_number': (float,),  # noqa: E501
         'attribute_integer': (int,),  # noqa: E501