implement example

examples/postly/lib/data/model/post_model.dart

@@ -0,0 +1,16 @@
+import 'package:freezed_annotation/freezed_annotation.dart';
+
+part 'post_model.freezed.dart';
+part 'post_model.g.dart';
+
+@freezed
+class PostModel with _$PostModel {
+  const factory PostModel({
+    required int id,
+    required String title,
+    required String body,
+  }) = _PostModel;
+
+  factory PostModel.fromJson(Map<String, dynamic> json) =>
+      _$PostModelFromJson(json);
+}