doc(Python): Document TODO to refactor string conversion (#587)

Author: lucasmcdonald3

codegen/smithy-dafny-codegen/src/main/java/software/amazon/polymorph/smithypython/awssdk/shapevisitor/AwsSdkToDafnyShapeVisitor.java

@@ -207,6 +207,8 @@ public String stringShape(StringShape shape) {
     }
 
     // Convert native Python string to Dafny Seq of UTF-16 characters
+    // TODO: This is a long conversion that is used often in generated code, since this is written for *all* strings.
+    // This should be refactored into the conversionwriter package.
     return "Seq(''.join([chr(int.from_bytes(pair, 'big')) for pair in zip(*[iter(%1$s.encode('utf-16-be'))]*2)]))".formatted(
         dataSource
       );

codegen/smithy-dafny-codegen/src/main/java/software/amazon/polymorph/smithypython/awssdk/shapevisitor/DafnyToAwsSdkShapeVisitor.java

@@ -194,6 +194,8 @@ public String stringShape(StringShape shape) {
       return enumShape(EnumShape.fromStringShape(shape).get());
     }
     // Convert Dafny Seq of UTF-16 characters to native Python string
+    // TODO: This is a long conversion that is used often in generated code, since this is written for *all* strings.
+    // This should be refactored into the conversionwriter package.
     return "b''.join(ord(c).to_bytes(2, 'big') for c in %1$s).decode('utf-16-be')".formatted(
         dataSource
       );

codegen/smithy-dafny-codegen/src/main/java/software/amazon/polymorph/smithypython/localservice/shapevisitor/DafnyToLocalServiceShapeVisitor.java

@@ -244,6 +244,8 @@ public String stringShape(StringShape shape) {
       return "bytes(%1$s.Elements).decode('utf-8')".formatted(dataSource);
     }
     // Convert Dafny Seq of UTF-16 characters to native Python string
+    // TODO: This is a long conversion that is used often in generated code, since this is written for *all* strings.
+    // This should be refactored into the conversionwriter package.
     return "b''.join(ord(c).to_bytes(2, 'big') for c in %1$s).decode('utf-16-be')".formatted(
         dataSource
       );

codegen/smithy-dafny-codegen/src/main/java/software/amazon/polymorph/smithypython/localservice/shapevisitor/LocalServiceToDafnyShapeVisitor.java

@@ -246,6 +246,8 @@ public String stringShape(StringShape shape) {
       return "Seq(%1$s.encode('utf-8'))".formatted(dataSource);
     }
     // Convert native Python string to Dafny Seq of UTF-16 characters
+    // TODO: This is a long conversion that is used often in generated code, since this is written for *all* strings.
+    // This should be refactored into the conversionwriter package.
     return "Seq(''.join([chr(int.from_bytes(pair, 'big')) for pair in zip(*[iter(%1$s.encode('utf-16-be'))]*2)]))".formatted(
         dataSource
       );