fix(python): fix snippet regressions in reference.md and docstrings

generators/python-v2/dynamic-snippets/src/__test__/__snapshots__/DynamicSnippetsGenerator.test.ts.snap

@@ -38,6 +38,7 @@ client.service.get_metadata(
 exports[`snippets > examples > 'POST /big-entity (simple)' 1`] = `
 "from acme import Acme
 from acme.types import Actor, ExtendedMovie, Migration
+from acme.commons.types import EventInfo_Metadata
 
 client = Acme(
     token="<YOUR_API_KEY>",
@@ -68,15 +69,14 @@ client.service.create_big_entity(
         },
         revenue=1000000,
     ),
-    event_info={
-        "type": "metadata",
-        "id": "event-12345",
-        "data": {
+    event_info=EventInfo_Metadata(
+        id="event-12345",
+        data={
             "key1": "val1",
             "key2": "val2"
         },
-        "json_string": "abc"
-    },
+        json_string="abc",
+    ),
     migration=Migration(
         name="Migration 31 Aug",
         status="RUNNING",

generators/python-v2/dynamic-snippets/src/context/DynamicSnippetsGeneratorContext.ts

@@ -93,6 +93,22 @@ export class DynamicSnippetsGeneratorContext extends AbstractDynamicSnippetsGene
         return python.reference({ name: className, modulePath });
     }
 
+    public getDiscriminatedUnionVariantClassReference({
+        unionDeclaration,
+        discriminantValue
+    }: {
+        unionDeclaration: FernIr.dynamic.Declaration;
+        discriminantValue: FernIr.dynamic.NameAndWireValue;
+    }): python.Reference {
+        const unionClassName = this.getClassName(unionDeclaration.name);
+        const variantSuffix = discriminantValue.name.pascalCase.safeName;
+        const modulePath = [
+            ...this.getRootModulePath(),
+            ...unionDeclaration.fernFilepath.allParts.map((part) => part.snakeCase.safeName)
+        ];
+        return python.reference({ name: `${unionClassName}_${variantSuffix}`, modulePath });
+    }
+
     public useTypedDictRequests(): boolean {
         return this.customConfig.use_typeddict_requests === true;
     }

generators/python-v2/dynamic-snippets/src/context/DynamicTypeLiteralMapper.ts

@@ -226,11 +226,19 @@ export class DynamicTypeLiteralMapper {
         if (unionProperties == null) {
             return python.TypeInstantiation.nop();
         }
-        const discriminantProperty = {
-            name: this.context.getPropertyName(discriminatedUnion.discriminant.name),
-            value: python.TypeInstantiation.str(unionVariant.discriminantValue.wireValue)
-        };
-        return python.TypeInstantiation.typedDict([discriminantProperty, ...unionProperties], { multiline: true });
+        const variantClassReference = this.context.getDiscriminatedUnionVariantClassReference({
+            unionDeclaration: discriminatedUnion.declaration,
+            discriminantValue: unionVariant.discriminantValue
+        });
+        return python.TypeInstantiation.reference(
+            python.instantiateClass({
+                classReference: variantClassReference,
+                arguments_: unionProperties.map((entry) =>
+                    python.methodArgument({ name: entry.name, value: entry.value })
+                ),
+                multiline: true
+            })
+        );
     }
 
     private convertDiscriminatedUnionProperties({
@@ -387,13 +395,6 @@ export class DynamicTypeLiteralMapper {
         value: unknown;
     }): python.TypeInstantiation {
         const entries = this.convertObjectEntries({ object_, value });
-
-        // biome-ignore lint/correctness/useHookAtTopLevel: not a React hook
-        if (this.context.useTypedDictRequests()) {
-            return python.TypeInstantiation.typedDict(entries, { multiline: true });
-        }
-
-        // Pydantic model style: ClassName(key=value)
         const classReference = this.context.getTypeClassReference(object_.declaration);
         return python.TypeInstantiation.reference(
             python.instantiateClass({
@@ -415,10 +416,27 @@ export class DynamicTypeLiteralMapper {
         if (enumValue == null) {
             return python.TypeInstantiation.nop();
         }
-        return python.TypeInstantiation.str(enumValue);
+        const enumType = this.context.customConfig.pydantic_config?.enum_type;
+        if (enumType === "python_enums" || enumType === "forward_compatible_python_enums") {
+            const classReference = this.context.getTypeClassReference(enum_.declaration);
+            const memberName = enumValue.name.screamingSnakeCase.safeName;
+            return python.TypeInstantiation.reference(
+                python.accessAttribute({
+                    lhs: classReference,
+                    rhs: python.codeBlock(memberName)
+                })
+            );
+        }
+        return python.TypeInstantiation.str(enumValue.wireValue);
     }
 
-    private getEnumValue({ enum_, value }: { enum_: FernIr.dynamic.EnumType; value: unknown }): string | undefined {
+    private getEnumValue({
+        enum_,
+        value
+    }: {
+        enum_: FernIr.dynamic.EnumType;
+        value: unknown;
+    }): FernIr.dynamic.NameAndWireValue | undefined {
         if (typeof value !== "string") {
             this.context.errors.add({
                 severity: Severity.Critical,
@@ -434,7 +452,7 @@ export class DynamicTypeLiteralMapper {
             });
             return undefined;
         }
-        return value;
+        return enumValue;
     }
 
     private convertUndiscriminatedUnion({
@@ -586,6 +604,17 @@ export class DynamicTypeLiteralMapper {
                 if (firstValue == null) {
                     return python.TypeInstantiation.nop();
                 }
+                const enumType = this.context.customConfig.pydantic_config?.enum_type;
+                if (enumType === "python_enums" || enumType === "forward_compatible_python_enums") {
+                    const classReference = this.context.getTypeClassReference(named.declaration);
+                    const memberName = firstValue.name.screamingSnakeCase.safeName;
+                    return python.TypeInstantiation.reference(
+                        python.accessAttribute({
+                            lhs: classReference,
+                            rhs: python.codeBlock(memberName)
+                        })
+                    );
+                }
                 return python.TypeInstantiation.str(firstValue.wireValue);
             }
             case "object": {
@@ -605,10 +634,6 @@ export class DynamicTypeLiteralMapper {
                         });
                     }
                 }
-                // biome-ignore lint/correctness/useHookAtTopLevel: not a React hook
-                if (this.context.useTypedDictRequests()) {
-                    return python.TypeInstantiation.typedDict(entries, { multiline: true });
-                }
                 const classReference = this.context.getTypeClassReference(named.declaration);
                 return python.TypeInstantiation.reference(
                     python.instantiateClass({

generators/python-v2/sdk/src/SdkGeneratorCli.ts

@@ -110,7 +110,10 @@ export class SdkGeneratorCli extends AbstractPythonGeneratorCli<SdkCustomConfigS
             config: {
                 organization: context.config.organization,
                 workspaceName: context.config.workspaceName,
-                customConfig: context.customConfig
+                // Pass the raw customConfig (not the parsed SdkCustomConfigSchema) so that
+                // fields consumed by the dynamic snippets generator (e.g. pydantic_config)
+                // are preserved. SdkCustomConfigSchema.parse() strips unknown keys.
+                customConfig: context.config.customConfig
             } as FernGeneratorExec.GeneratorConfig
         });
 

generators/python/sdk/versions.yml

@@ -1,5 +1,24 @@
 # yaml-language-server: $schema=../../../fern-versions-yml.schema.json
 # For unreleased changes, use unreleased.yml
+- version: 5.3.2
+  changelogEntry:
+    - summary: |
+        Fix enum values in reference.md and README snippets being rendered as string
+        literals instead of enum references when using `python_enums` or
+        `forward_compatible_python_enums` pydantic config.
+      type: fix
+    - summary: |
+        Fix client_id and client_secret parameters missing from OAuth client credentials
+        client instantiation examples in docstrings.
+      type: fix
+    - summary: |
+        Fix objects and discriminated unions in reference.md and README snippets being
+        rendered as dict literals instead of Pydantic model constructors. For example,
+        `order_type=OrderType_Market()` instead of `order_type={"type": "MARKET"}`.
+      type: fix
+  createdAt: "2026-04-06"
+  irVersion: 65
+
 - version: 5.3.1
   changelogEntry:
     - summary: |

generators/python/src/fern_python/generators/sdk/client_generator/root_client_generator.py

@@ -1704,6 +1704,7 @@ def build_default_snippet_kwargs() -> List[typing.Tuple[str, AST.Expression]]:
                 - Use kwargs (many root client params are keyword-only).
                 - Include required parameters (those without defaults) with reasonable placeholders.
                 - Prefer inferred-auth credentials (e.g. api_key) when present.
+                - Include client_id/client_secret for OAuth client credentials flows.
                 """
 
                 required_params = [
@@ -1737,6 +1738,15 @@ def build_default_snippet_kwargs() -> List[typing.Tuple[str, AST.Expression]]:
 
                     kwargs.append((name, AST.Expression(f'"YOUR_{name.upper()}"')))
 
+                # For OAuth client credentials, explicitly include client_id and client_secret
+                # even though they have os.getenv() defaults.
+                if self._oauth_token_override:
+                    oauth_param_names_in_kwargs = {name for name, _ in kwargs}
+                    if "client_id" not in oauth_param_names_in_kwargs:
+                        kwargs.append(("client_id", AST.Expression('"YOUR_CLIENT_ID"')))
+                    if "client_secret" not in oauth_param_names_in_kwargs:
+                        kwargs.append(("client_secret", AST.Expression('"YOUR_CLIENT_SECRET"')))
+
                 return kwargs
 
             if self._use_kwargs_snippets: