diff --git a/01.workspace/heave/src/str/entity.rs b/01.workspace/heave/src/str/entity.rs
index 30e0ebf..e080a3c 100644
--- a/01.workspace/heave/src/str/entity.rs
+++ b/01.workspace/heave/src/str/entity.rs
@@ -64,6 +64,12 @@ impl O {
             .map(|value| T::from(value.clone()))
             .unwrap()
     }
+    pub fn unwrap_opt<T>(&self, id: &str) -> Option<T>
+    where
+        T: From<Value>,
+    {
+        self.value_of(id).map(|value| T::from(value.clone()))
+    }
     pub fn unwrap_or<T>(&self, id: &str, default: T) -> T
     where
         T: From<Value>,