fix: quote recursive union member annotations

codegen/build.gradle.kts

@@ -15,5 +15,5 @@
 
 allprojects {
     group = "software.amazon.smithy.python"
-    version = "0.3.0"
+    version = "0.3.1"
 }

codegen/core/src/it/resources/META-INF/smithy/main.smithy

@@ -305,6 +305,8 @@ operation ListCities {
         sparseItems: SparseCitySummaries
 
         mutual: MutuallyRecursiveA
+
+        recursiveUnion: RecursiveUnion
     }
 }
 
@@ -567,6 +569,21 @@ structure MutuallyRecursiveB {
     mutual: MutuallyRecursiveA
 }
 
+union RecursiveUnion {
+    nested: RecursiveUnionMap
+    items: RecursiveUnionList
+    leaf: String
+}
+
+map RecursiveUnionMap {
+    key: String
+    value: RecursiveUnion
+}
+
+list RecursiveUnionList {
+    member: RecursiveUnion
+}
+
 // CitySummaries is a list of CitySummary structures.
 list CitySummaries {
     member: CitySummary

codegen/core/src/main/java/software/amazon/smithy/python/codegen/generators/UnionGenerator.java

@@ -62,12 +62,14 @@ public void run() {
 
             var target = model.expectShape(member.getTarget());
             var targetSymbol = symbolProvider.toSymbol(target);
+            writer.pushState();
+            writer.putContext("quote", recursiveShapes.contains(target) ? "'" : "");
             writer.write("""
                     @dataclass
                     class $1L:
                         ${2C|}
 
-                        value: $3T
+                        value: ${quote:L}$3T${quote:L}
 
                         def serialize(self, serializer: ShapeSerializer):
                             serializer.write_struct($4T, self)
@@ -92,6 +94,7 @@ def deserialize(cls, deserializer: ShapeDeserializer) -> Self:
                             new MemberDeserializerGenerator(context, w, member, "deserializer")))
 
             );
+            writer.popState();
         }
 
         // Note that the unknown variant doesn't implement __eq__. This is because