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 f156a44e6e99..9c4bd3bbb92d 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
@@ -723,11 +723,11 @@ public CodegenModel fromModel(String name, Schema sc) {
         // 1. no default exists
         //      schema does not contain default
         //      cm.defaultValue unset, cm.hasRequired = true
-        // 2. server has a default
+        // 2. spec has a default
         //      schema contains default
-        //      cm.defaultValue set, cm.hasRequired = true
+        //      cm.defaultValue set, cm.hasRequired = false
         //      different value here to differentiate between use case 3 below
-        //      This defaultValue is used in the client docs only and is not sent to the server
+        //      This defaultValue is used when a consumer (client or server) lacks the input argument, defaultValue will be used
         // 3. only one value is allowed in an enum
         //      schema does not contain default
         //      cm.defaultValue set, cm.hasRequired = false
@@ -738,7 +738,7 @@ public CodegenModel fromModel(String name, Schema sc) {
             cm.hasRequired = true;
         } else if (sc.getDefault() != null) {
             cm.defaultValue = defaultValue;
-            cm.hasRequired = true;
+            cm.hasRequired = false;
         } else if (defaultValue != null && cm.defaultValue == null) {
             cm.defaultValue = defaultValue;
             cm.hasRequired = false;
diff --git a/modules/openapi-generator/src/main/resources/python/python-experimental/model_templates/method_init_simple.mustache b/modules/openapi-generator/src/main/resources/python/python-experimental/model_templates/method_init_simple.mustache
index 9d59b7ba0914..b71b80667c06 100644
--- a/modules/openapi-generator/src/main/resources/python/python-experimental/model_templates/method_init_simple.mustache
+++ b/modules/openapi-generator/src/main/resources/python/python-experimental/model_templates/method_init_simple.mustache
@@ -8,30 +8,37 @@
     ])
 
     @convert_js_args_to_python_args
-    def __init__(self{{#hasRequired}}, value{{/hasRequired}}, *args, **kwargs):
+    def __init__(self, *args, **kwargs):
         """{{classname}} - a model defined in OpenAPI
 
-{{#hasRequired}}
+        Note that value can be passed either in args or in kwargs, but not in both.
+
         Args:
-            value ({{{dataType}}}):{{#description}} {{description}}.{{/description}}{{#defaultValue}} if omitted the server will use the default value of {{{defaultValue}}}{{/defaultValue}}{{#allowableValues}}, must be one of [{{#enumVars}}{{{value}}}, {{/enumVars}}]{{/allowableValues}}  # noqa: E501
+            args[0] ({{{dataType}}}):{{#description}} {{description}}.{{/description}}{{#defaultValue}} if omitted defaults to {{{defaultValue}}}{{/defaultValue}}{{#allowableValues}}, must be one of [{{#enumVars}}{{{value}}}, {{/enumVars}}]{{/allowableValues}}  # noqa: E501
 
-{{/hasRequired}}
         Keyword Args:
-{{^hasRequired}}
-            value ({{{dataType}}}):{{#description}} {{description}}.{{/description}}{{#defaultValue}} defaults to {{{defaultValue}}}{{/defaultValue}}{{#allowableValues}}, must be one of [{{#enumVars}}{{{value}}}, {{/enumVars}}]{{/allowableValues}}  # noqa: E501
-{{/hasRequired}}
+            value ({{{dataType}}}):{{#description}} {{description}}.{{/description}}{{#defaultValue}} if omitted defaults to {{{defaultValue}}}{{/defaultValue}}{{#allowableValues}}, must be one of [{{#enumVars}}{{{value}}}, {{/enumVars}}]{{/allowableValues}}  # noqa: E501
 {{> python-experimental/model_templates/docstring_init_required_kwargs }}
         """
 
-{{^hasRequired}}
         if 'value' in kwargs:
             value = kwargs.pop('value')
         elif args:
             args = list(args)
             value = args.pop(0)
+{{#defaultValue}}
         else:
             value = {{{defaultValue}}}
-{{/hasRequired}}
+{{/defaultValue}}
+{{^defaultValue}}
+        else:
+            raise ApiTypeError(
+                "value is required, but not passed in args or kwargs and doesn't have default",
+                path_to_item=_path_to_item,
+                valid_classes=(self.__class__,),
+            )
+{{/defaultValue}}
+
         _check_type = kwargs.pop('_check_type', True)
         _spec_property_naming = kwargs.pop('_spec_property_naming', False)
         _path_to_item = kwargs.pop('_path_to_item', ())
diff --git a/modules/openapi-generator/src/test/java/org/openapitools/codegen/python/PythonClientExperimentalTest.java b/modules/openapi-generator/src/test/java/org/openapitools/codegen/python/PythonClientExperimentalTest.java
index 4807ea2f3ceb..093598d02ce4 100644
--- a/modules/openapi-generator/src/test/java/org/openapitools/codegen/python/PythonClientExperimentalTest.java
+++ b/modules/openapi-generator/src/test/java/org/openapitools/codegen/python/PythonClientExperimentalTest.java
@@ -375,7 +375,7 @@ public void defaultSettingInPrimitiveModelWithValidations() {
 
         final CodegenModel hasDefaultModel = codegen.fromModel("hasDefaultModel", hasDefault);
         Assert.assertEquals(hasDefaultModel.defaultValue, "15.0");
-        Assert.assertEquals(hasDefaultModel.hasRequired, true);
+        Assert.assertEquals(hasDefaultModel.hasRequired, false);
 
         final CodegenModel noDefaultEumLengthOneModel = codegen.fromModel("noDefaultEumLengthOneModel", noDefaultEumLengthOne);
         Assert.assertEquals(noDefaultEumLengthOneModel.defaultValue, "15.0");
diff --git a/samples/client/petstore/python-experimental/docs/EnumClass.md b/samples/client/petstore/python-experimental/docs/EnumClass.md
index 6c5c0619a1b0..6dda7fd8a77f 100644
--- a/samples/client/petstore/python-experimental/docs/EnumClass.md
+++ b/samples/client/petstore/python-experimental/docs/EnumClass.md
@@ -3,7 +3,7 @@
 ## Properties
 Name | Type | Description | Notes
 ------------ | ------------- | ------------- | -------------
-**value** | **str** |  |  if omitted the server will use the default value of "-efg",  must be one of ["_abc", "-efg", "(xyz)", ]
+**value** | **str** |  | defaults to "-efg",  must be one of ["_abc", "-efg", "(xyz)", ]
 
 [[Back to Model list]](../README.md#documentation-for-models) [[Back to API list]](../README.md#documentation-for-api-endpoints) [[Back to README]](../README.md)
 
diff --git a/samples/client/petstore/python-experimental/petstore_api/model/animal_farm.py b/samples/client/petstore/python-experimental/petstore_api/model/animal_farm.py
index dc35f9394e1c..bf7bbf04c38f 100644
--- a/samples/client/petstore/python-experimental/petstore_api/model/animal_farm.py
+++ b/samples/client/petstore/python-experimental/petstore_api/model/animal_farm.py
@@ -99,13 +99,16 @@ def discriminator():
     ])
 
     @convert_js_args_to_python_args
-    def __init__(self, value, *args, **kwargs):
+    def __init__(self, *args, **kwargs):
         """AnimalFarm - a model defined in OpenAPI
 
+        Note that value can be passed either in args or in kwargs, but not in both.
+
         Args:
-            value ([Animal]):  # noqa: E501
+            args[0] ([Animal]):  # noqa: E501
 
         Keyword Args:
+            value ([Animal]):  # noqa: E501
             _check_type (bool): if True, values for parameters in openapi_types
                                 will be type checked and a TypeError will be
                                 raised if the wrong type is input.
@@ -138,6 +141,18 @@ def __init__(self, value, *args, **kwargs):
                                 _visited_composed_classes = (Animal,)
         """
 
+        if 'value' in kwargs:
+            value = kwargs.pop('value')
+        elif args:
+            args = list(args)
+            value = args.pop(0)
+        else:
+            raise ApiTypeError(
+                "value is required, but not passed in args or kwargs and doesn't have default",
+                path_to_item=_path_to_item,
+                valid_classes=(self.__class__,),
+            )
+
         _check_type = kwargs.pop('_check_type', True)
         _spec_property_naming = kwargs.pop('_spec_property_naming', False)
         _path_to_item = kwargs.pop('_path_to_item', ())
diff --git a/samples/client/petstore/python-experimental/petstore_api/model/enum_class.py b/samples/client/petstore/python-experimental/petstore_api/model/enum_class.py
index 2052f27748f0..208019cfe111 100644
--- a/samples/client/petstore/python-experimental/petstore_api/model/enum_class.py
+++ b/samples/client/petstore/python-experimental/petstore_api/model/enum_class.py
@@ -99,13 +99,16 @@ def discriminator():
     ])
 
     @convert_js_args_to_python_args
-    def __init__(self, value, *args, **kwargs):
+    def __init__(self, *args, **kwargs):
         """EnumClass - a model defined in OpenAPI
 
+        Note that value can be passed either in args or in kwargs, but not in both.
+
         Args:
-            value (str): if omitted the server will use the default value of "-efg", must be one of ["_abc", "-efg", "(xyz)", ]  # noqa: E501
+            args[0] (str): if omitted defaults to "-efg", must be one of ["_abc", "-efg", "(xyz)", ]  # noqa: E501
 
         Keyword Args:
+            value (str): if omitted defaults to "-efg", must be one of ["_abc", "-efg", "(xyz)", ]  # noqa: E501
             _check_type (bool): if True, values for parameters in openapi_types
                                 will be type checked and a TypeError will be
                                 raised if the wrong type is input.
@@ -138,6 +141,14 @@ def __init__(self, value, *args, **kwargs):
                                 _visited_composed_classes = (Animal,)
         """
 
+        if 'value' in kwargs:
+            value = kwargs.pop('value')
+        elif args:
+            args = list(args)
+            value = args.pop(0)
+        else:
+            value = "-efg"
+
         _check_type = kwargs.pop('_check_type', True)
         _spec_property_naming = kwargs.pop('_spec_property_naming', False)
         _path_to_item = kwargs.pop('_path_to_item', ())
diff --git a/samples/client/petstore/python-experimental/petstore_api/model/number_with_validations.py b/samples/client/petstore/python-experimental/petstore_api/model/number_with_validations.py
index 00656ce8bcf7..51e7dece4b27 100644
--- a/samples/client/petstore/python-experimental/petstore_api/model/number_with_validations.py
+++ b/samples/client/petstore/python-experimental/petstore_api/model/number_with_validations.py
@@ -98,13 +98,16 @@ def discriminator():
     ])
 
     @convert_js_args_to_python_args
-    def __init__(self, value, *args, **kwargs):
+    def __init__(self, *args, **kwargs):
         """NumberWithValidations - a model defined in OpenAPI
 
+        Note that value can be passed either in args or in kwargs, but not in both.
+
         Args:
-            value (float):  # noqa: E501
+            args[0] (float):  # noqa: E501
 
         Keyword Args:
+            value (float):  # noqa: E501
             _check_type (bool): if True, values for parameters in openapi_types
                                 will be type checked and a TypeError will be
                                 raised if the wrong type is input.
@@ -137,6 +140,18 @@ def __init__(self, value, *args, **kwargs):
                                 _visited_composed_classes = (Animal,)
         """
 
+        if 'value' in kwargs:
+            value = kwargs.pop('value')
+        elif args:
+            args = list(args)
+            value = args.pop(0)
+        else:
+            raise ApiTypeError(
+                "value is required, but not passed in args or kwargs and doesn't have default",
+                path_to_item=_path_to_item,
+                valid_classes=(self.__class__,),
+            )
+
         _check_type = kwargs.pop('_check_type', True)
         _spec_property_naming = kwargs.pop('_spec_property_naming', False)
         _path_to_item = kwargs.pop('_path_to_item', ())
diff --git a/samples/client/petstore/python-experimental/petstore_api/model/string_enum.py b/samples/client/petstore/python-experimental/petstore_api/model/string_enum.py
index 1fd2b6746989..8d8be9601454 100644
--- a/samples/client/petstore/python-experimental/petstore_api/model/string_enum.py
+++ b/samples/client/petstore/python-experimental/petstore_api/model/string_enum.py
@@ -99,13 +99,16 @@ def discriminator():
     ])
 
     @convert_js_args_to_python_args
-    def __init__(self, value, *args, **kwargs):
+    def __init__(self, *args, **kwargs):
         """StringEnum - a model defined in OpenAPI
 
+        Note that value can be passed either in args or in kwargs, but not in both.
+
         Args:
-            value (str):, must be one of ["placed", "approved", "delivered", ]  # noqa: E501
+            args[0] (str):, must be one of ["placed", "approved", "delivered", ]  # noqa: E501
 
         Keyword Args:
+            value (str):, must be one of ["placed", "approved", "delivered", ]  # noqa: E501
             _check_type (bool): if True, values for parameters in openapi_types
                                 will be type checked and a TypeError will be
                                 raised if the wrong type is input.
@@ -138,6 +141,18 @@ def __init__(self, value, *args, **kwargs):
                                 _visited_composed_classes = (Animal,)
         """
 
+        if 'value' in kwargs:
+            value = kwargs.pop('value')
+        elif args:
+            args = list(args)
+            value = args.pop(0)
+        else:
+            raise ApiTypeError(
+                "value is required, but not passed in args or kwargs and doesn't have default",
+                path_to_item=_path_to_item,
+                valid_classes=(self.__class__,),
+            )
+
         _check_type = kwargs.pop('_check_type', True)
         _spec_property_naming = kwargs.pop('_spec_property_naming', False)
         _path_to_item = kwargs.pop('_path_to_item', ())
diff --git a/samples/openapi3/client/petstore/python-experimental/docs/EnumClass.md b/samples/openapi3/client/petstore/python-experimental/docs/EnumClass.md
index 6c5c0619a1b0..6dda7fd8a77f 100644
--- a/samples/openapi3/client/petstore/python-experimental/docs/EnumClass.md
+++ b/samples/openapi3/client/petstore/python-experimental/docs/EnumClass.md
@@ -3,7 +3,7 @@
 ## Properties
 Name | Type | Description | Notes
 ------------ | ------------- | ------------- | -------------
-**value** | **str** |  |  if omitted the server will use the default value of "-efg",  must be one of ["_abc", "-efg", "(xyz)", ]
+**value** | **str** |  | defaults to "-efg",  must be one of ["_abc", "-efg", "(xyz)", ]
 
 [[Back to Model list]](../README.md#documentation-for-models) [[Back to API list]](../README.md#documentation-for-api-endpoints) [[Back to README]](../README.md)
 
diff --git a/samples/openapi3/client/petstore/python-experimental/docs/IntegerEnumWithDefaultValue.md b/samples/openapi3/client/petstore/python-experimental/docs/IntegerEnumWithDefaultValue.md
index b2ae7cef0d36..9988294c0373 100644
--- a/samples/openapi3/client/petstore/python-experimental/docs/IntegerEnumWithDefaultValue.md
+++ b/samples/openapi3/client/petstore/python-experimental/docs/IntegerEnumWithDefaultValue.md
@@ -3,7 +3,7 @@
 ## Properties
 Name | Type | Description | Notes
 ------------ | ------------- | ------------- | -------------
-**value** | **int** |  |  if omitted the server will use the default value of 0,  must be one of [0, 1, 2, ]
+**value** | **int** |  | defaults to 0,  must be one of [0, 1, 2, ]
 
 [[Back to Model list]](../README.md#documentation-for-models) [[Back to API list]](../README.md#documentation-for-api-endpoints) [[Back to README]](../README.md)
 
diff --git a/samples/openapi3/client/petstore/python-experimental/docs/StringEnumWithDefaultValue.md b/samples/openapi3/client/petstore/python-experimental/docs/StringEnumWithDefaultValue.md
index 74cc456c84f9..13cc075ab34e 100644
--- a/samples/openapi3/client/petstore/python-experimental/docs/StringEnumWithDefaultValue.md
+++ b/samples/openapi3/client/petstore/python-experimental/docs/StringEnumWithDefaultValue.md
@@ -3,7 +3,7 @@
 ## Properties
 Name | Type | Description | Notes
 ------------ | ------------- | ------------- | -------------
-**value** | **str** |  |  if omitted the server will use the default value of "placed",  must be one of ["placed", "approved", "delivered", ]
+**value** | **str** |  | defaults to "placed",  must be one of ["placed", "approved", "delivered", ]
 
 [[Back to Model list]](../README.md#documentation-for-models) [[Back to API list]](../README.md#documentation-for-api-endpoints) [[Back to README]](../README.md)
 
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/model/animal_farm.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/animal_farm.py
index dc35f9394e1c..bf7bbf04c38f 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/model/animal_farm.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/animal_farm.py
@@ -99,13 +99,16 @@ def discriminator():
     ])
 
     @convert_js_args_to_python_args
-    def __init__(self, value, *args, **kwargs):
+    def __init__(self, *args, **kwargs):
         """AnimalFarm - a model defined in OpenAPI
 
+        Note that value can be passed either in args or in kwargs, but not in both.
+
         Args:
-            value ([Animal]):  # noqa: E501
+            args[0] ([Animal]):  # noqa: E501
 
         Keyword Args:
+            value ([Animal]):  # noqa: E501
             _check_type (bool): if True, values for parameters in openapi_types
                                 will be type checked and a TypeError will be
                                 raised if the wrong type is input.
@@ -138,6 +141,18 @@ def __init__(self, value, *args, **kwargs):
                                 _visited_composed_classes = (Animal,)
         """
 
+        if 'value' in kwargs:
+            value = kwargs.pop('value')
+        elif args:
+            args = list(args)
+            value = args.pop(0)
+        else:
+            raise ApiTypeError(
+                "value is required, but not passed in args or kwargs and doesn't have default",
+                path_to_item=_path_to_item,
+                valid_classes=(self.__class__,),
+            )
+
         _check_type = kwargs.pop('_check_type', True)
         _spec_property_naming = kwargs.pop('_spec_property_naming', False)
         _path_to_item = kwargs.pop('_path_to_item', ())
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/model/array_of_enums.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/array_of_enums.py
index 7de4cae7f1eb..afcea8b9303d 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/model/array_of_enums.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/array_of_enums.py
@@ -99,13 +99,16 @@ def discriminator():
     ])
 
     @convert_js_args_to_python_args
-    def __init__(self, value, *args, **kwargs):
+    def __init__(self, *args, **kwargs):
         """ArrayOfEnums - a model defined in OpenAPI
 
+        Note that value can be passed either in args or in kwargs, but not in both.
+
         Args:
-            value ([StringEnum]):  # noqa: E501
+            args[0] ([StringEnum]):  # noqa: E501
 
         Keyword Args:
+            value ([StringEnum]):  # noqa: E501
             _check_type (bool): if True, values for parameters in openapi_types
                                 will be type checked and a TypeError will be
                                 raised if the wrong type is input.
@@ -138,6 +141,18 @@ def __init__(self, value, *args, **kwargs):
                                 _visited_composed_classes = (Animal,)
         """
 
+        if 'value' in kwargs:
+            value = kwargs.pop('value')
+        elif args:
+            args = list(args)
+            value = args.pop(0)
+        else:
+            raise ApiTypeError(
+                "value is required, but not passed in args or kwargs and doesn't have default",
+                path_to_item=_path_to_item,
+                valid_classes=(self.__class__,),
+            )
+
         _check_type = kwargs.pop('_check_type', True)
         _spec_property_naming = kwargs.pop('_spec_property_naming', False)
         _path_to_item = kwargs.pop('_path_to_item', ())
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/model/enum_class.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/enum_class.py
index 2052f27748f0..208019cfe111 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/model/enum_class.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/enum_class.py
@@ -99,13 +99,16 @@ def discriminator():
     ])
 
     @convert_js_args_to_python_args
-    def __init__(self, value, *args, **kwargs):
+    def __init__(self, *args, **kwargs):
         """EnumClass - a model defined in OpenAPI
 
+        Note that value can be passed either in args or in kwargs, but not in both.
+
         Args:
-            value (str): if omitted the server will use the default value of "-efg", must be one of ["_abc", "-efg", "(xyz)", ]  # noqa: E501
+            args[0] (str): if omitted defaults to "-efg", must be one of ["_abc", "-efg", "(xyz)", ]  # noqa: E501
 
         Keyword Args:
+            value (str): if omitted defaults to "-efg", must be one of ["_abc", "-efg", "(xyz)", ]  # noqa: E501
             _check_type (bool): if True, values for parameters in openapi_types
                                 will be type checked and a TypeError will be
                                 raised if the wrong type is input.
@@ -138,6 +141,14 @@ def __init__(self, value, *args, **kwargs):
                                 _visited_composed_classes = (Animal,)
         """
 
+        if 'value' in kwargs:
+            value = kwargs.pop('value')
+        elif args:
+            args = list(args)
+            value = args.pop(0)
+        else:
+            value = "-efg"
+
         _check_type = kwargs.pop('_check_type', True)
         _spec_property_naming = kwargs.pop('_spec_property_naming', False)
         _path_to_item = kwargs.pop('_path_to_item', ())
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/model/integer_enum.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/integer_enum.py
index 67d924c427c0..43abd8e0286d 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/model/integer_enum.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/integer_enum.py
@@ -99,13 +99,16 @@ def discriminator():
     ])
 
     @convert_js_args_to_python_args
-    def __init__(self, value, *args, **kwargs):
+    def __init__(self, *args, **kwargs):
         """IntegerEnum - a model defined in OpenAPI
 
+        Note that value can be passed either in args or in kwargs, but not in both.
+
         Args:
-            value (int):, must be one of [0, 1, 2, ]  # noqa: E501
+            args[0] (int):, must be one of [0, 1, 2, ]  # noqa: E501
 
         Keyword Args:
+            value (int):, must be one of [0, 1, 2, ]  # noqa: E501
             _check_type (bool): if True, values for parameters in openapi_types
                                 will be type checked and a TypeError will be
                                 raised if the wrong type is input.
@@ -138,6 +141,18 @@ def __init__(self, value, *args, **kwargs):
                                 _visited_composed_classes = (Animal,)
         """
 
+        if 'value' in kwargs:
+            value = kwargs.pop('value')
+        elif args:
+            args = list(args)
+            value = args.pop(0)
+        else:
+            raise ApiTypeError(
+                "value is required, but not passed in args or kwargs and doesn't have default",
+                path_to_item=_path_to_item,
+                valid_classes=(self.__class__,),
+            )
+
         _check_type = kwargs.pop('_check_type', True)
         _spec_property_naming = kwargs.pop('_spec_property_naming', False)
         _path_to_item = kwargs.pop('_path_to_item', ())
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/model/integer_enum_one_value.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/integer_enum_one_value.py
index 2ce011ae21dd..9df9dd15a5f9 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/model/integer_enum_one_value.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/integer_enum_one_value.py
@@ -100,8 +100,13 @@ def discriminator():
     def __init__(self, *args, **kwargs):
         """IntegerEnumOneValue - a model defined in OpenAPI
 
+        Note that value can be passed either in args or in kwargs, but not in both.
+
+        Args:
+            args[0] (int): if omitted defaults to 0, must be one of [0, ]  # noqa: E501
+
         Keyword Args:
-            value (int): defaults to 0, must be one of [0, ]  # noqa: E501
+            value (int): if omitted defaults to 0, must be one of [0, ]  # noqa: E501
             _check_type (bool): if True, values for parameters in openapi_types
                                 will be type checked and a TypeError will be
                                 raised if the wrong type is input.
@@ -141,6 +146,7 @@ def __init__(self, *args, **kwargs):
             value = args.pop(0)
         else:
             value = 0
+
         _check_type = kwargs.pop('_check_type', True)
         _spec_property_naming = kwargs.pop('_spec_property_naming', False)
         _path_to_item = kwargs.pop('_path_to_item', ())
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/model/integer_enum_with_default_value.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/integer_enum_with_default_value.py
index 04884c5dfdc3..3c325e399706 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/model/integer_enum_with_default_value.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/integer_enum_with_default_value.py
@@ -99,13 +99,16 @@ def discriminator():
     ])
 
     @convert_js_args_to_python_args
-    def __init__(self, value, *args, **kwargs):
+    def __init__(self, *args, **kwargs):
         """IntegerEnumWithDefaultValue - a model defined in OpenAPI
 
+        Note that value can be passed either in args or in kwargs, but not in both.
+
         Args:
-            value (int): if omitted the server will use the default value of 0, must be one of [0, 1, 2, ]  # noqa: E501
+            args[0] (int): if omitted defaults to 0, must be one of [0, 1, 2, ]  # noqa: E501
 
         Keyword Args:
+            value (int): if omitted defaults to 0, must be one of [0, 1, 2, ]  # noqa: E501
             _check_type (bool): if True, values for parameters in openapi_types
                                 will be type checked and a TypeError will be
                                 raised if the wrong type is input.
@@ -138,6 +141,14 @@ def __init__(self, value, *args, **kwargs):
                                 _visited_composed_classes = (Animal,)
         """
 
+        if 'value' in kwargs:
+            value = kwargs.pop('value')
+        elif args:
+            args = list(args)
+            value = args.pop(0)
+        else:
+            value = 0
+
         _check_type = kwargs.pop('_check_type', True)
         _spec_property_naming = kwargs.pop('_spec_property_naming', False)
         _path_to_item = kwargs.pop('_path_to_item', ())
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/model/number_with_validations.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/number_with_validations.py
index dac4ec635b81..feef9f4317a2 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/model/number_with_validations.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/number_with_validations.py
@@ -98,13 +98,16 @@ def discriminator():
     ])
 
     @convert_js_args_to_python_args
-    def __init__(self, value, *args, **kwargs):
+    def __init__(self, *args, **kwargs):
         """NumberWithValidations - a model defined in OpenAPI
 
+        Note that value can be passed either in args or in kwargs, but not in both.
+
         Args:
-            value (float):  # noqa: E501
+            args[0] (float):  # noqa: E501
 
         Keyword Args:
+            value (float):  # noqa: E501
             _check_type (bool): if True, values for parameters in openapi_types
                                 will be type checked and a TypeError will be
                                 raised if the wrong type is input.
@@ -137,6 +140,18 @@ def __init__(self, value, *args, **kwargs):
                                 _visited_composed_classes = (Animal,)
         """
 
+        if 'value' in kwargs:
+            value = kwargs.pop('value')
+        elif args:
+            args = list(args)
+            value = args.pop(0)
+        else:
+            raise ApiTypeError(
+                "value is required, but not passed in args or kwargs and doesn't have default",
+                path_to_item=_path_to_item,
+                valid_classes=(self.__class__,),
+            )
+
         _check_type = kwargs.pop('_check_type', True)
         _spec_property_naming = kwargs.pop('_spec_property_naming', False)
         _path_to_item = kwargs.pop('_path_to_item', ())
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/model/string_enum.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/string_enum.py
index 9c7ffa0854c8..2dee202bd3fc 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/model/string_enum.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/string_enum.py
@@ -105,15 +105,20 @@ def discriminator():
     ])
 
     @convert_js_args_to_python_args
-    def __init__(self, value, *args, **kwargs):
+    def __init__(self, *args, **kwargs):
         """StringEnum - a model defined in OpenAPI
 
+        Note that value can be passed either in args or in kwargs, but not in both.
+
         Args:
-            value (str):, must be one of ["placed", "approved", "delivered", "single quoted", '''multiple
+            args[0] (str):, must be one of ["placed", "approved", "delivered", "single quoted", '''multiple
 lines''', '''double quote 
  with newline''', ]  # noqa: E501
 
         Keyword Args:
+            value (str):, must be one of ["placed", "approved", "delivered", "single quoted", '''multiple
+lines''', '''double quote 
+ with newline''', ]  # noqa: E501
             _check_type (bool): if True, values for parameters in openapi_types
                                 will be type checked and a TypeError will be
                                 raised if the wrong type is input.
@@ -146,6 +151,18 @@ def __init__(self, value, *args, **kwargs):
                                 _visited_composed_classes = (Animal,)
         """
 
+        if 'value' in kwargs:
+            value = kwargs.pop('value')
+        elif args:
+            args = list(args)
+            value = args.pop(0)
+        else:
+            raise ApiTypeError(
+                "value is required, but not passed in args or kwargs and doesn't have default",
+                path_to_item=_path_to_item,
+                valid_classes=(self.__class__,),
+            )
+
         _check_type = kwargs.pop('_check_type', True)
         _spec_property_naming = kwargs.pop('_spec_property_naming', False)
         _path_to_item = kwargs.pop('_path_to_item', ())
diff --git a/samples/openapi3/client/petstore/python-experimental/petstore_api/model/string_enum_with_default_value.py b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/string_enum_with_default_value.py
index 7431e0d1d920..f25d079379d9 100644
--- a/samples/openapi3/client/petstore/python-experimental/petstore_api/model/string_enum_with_default_value.py
+++ b/samples/openapi3/client/petstore/python-experimental/petstore_api/model/string_enum_with_default_value.py
@@ -99,13 +99,16 @@ def discriminator():
     ])
 
     @convert_js_args_to_python_args
-    def __init__(self, value, *args, **kwargs):
+    def __init__(self, *args, **kwargs):
         """StringEnumWithDefaultValue - a model defined in OpenAPI
 
+        Note that value can be passed either in args or in kwargs, but not in both.
+
         Args:
-            value (str): if omitted the server will use the default value of "placed", must be one of ["placed", "approved", "delivered", ]  # noqa: E501
+            args[0] (str): if omitted defaults to "placed", must be one of ["placed", "approved", "delivered", ]  # noqa: E501
 
         Keyword Args:
+            value (str): if omitted defaults to "placed", must be one of ["placed", "approved", "delivered", ]  # noqa: E501
             _check_type (bool): if True, values for parameters in openapi_types
                                 will be type checked and a TypeError will be
                                 raised if the wrong type is input.
@@ -138,6 +141,14 @@ def __init__(self, value, *args, **kwargs):
                                 _visited_composed_classes = (Animal,)
         """
 
+        if 'value' in kwargs:
+            value = kwargs.pop('value')
+        elif args:
+            args = list(args)
+            value = args.pop(0)
+        else:
+            value = "placed"
+
         _check_type = kwargs.pop('_check_type', True)
         _spec_property_naming = kwargs.pop('_spec_property_naming', False)
         _path_to_item = kwargs.pop('_path_to_item', ())
diff --git a/samples/openapi3/client/petstore/python-experimental/testfiles/rsa.pem b/samples/openapi3/client/petstore/python-experimental/testfiles/rsa.pem
new file mode 100644
index 000000000000..ddc2c9767c4e
--- /dev/null
+++ b/samples/openapi3/client/petstore/python-experimental/testfiles/rsa.pem
@@ -0,0 +1,15 @@
+-----BEGIN RSA PRIVATE KEY-----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+-----END RSA PRIVATE KEY-----
\ No newline at end of file