new directory

lib/model/base_entity.dart

@@ -0,0 +1,19 @@
+abstract class BaseEntity{
+  static String id = 'id';
+  static String title = 'Title';
+  static String creationDate = 'CreationDate';
+  static String lastEditDate = 'LastEditDate';
+  
+  static String get getId{
+    return id;
+  }
+  static String get getTitle{
+    return title;
+  }
+  static String get getCreationDate{
+    return creationDate;
+  }
+  static String get getLastEditDate{
+    return lastEditDate;
+  }
+}