diff --git a/apis/python/operator/src/lib.rs b/apis/python/operator/src/lib.rs
index a57054eb9..c57960ea8 100644
--- a/apis/python/operator/src/lib.rs
+++ b/apis/python/operator/src/lib.rs
@@ -5,6 +5,7 @@ use pyo3::{exceptions::PyLookupError, prelude::*, types::PyDict};
 
 /// Dora Event
 #[pyclass]
+#[derive(Debug)]
 pub struct PyEvent {
     event: MergedEvent<PyObject>,
     data: Option<ArrayRef>,
@@ -56,6 +57,10 @@ impl PyEvent {
             MergedEvent::External(event) => Some(event),
         }
     }
+
+    fn __str__(&self) -> PyResult<String> {
+        Ok(format!("{:#?}", &self.event))
+    }
 }
 
 impl PyEvent {
diff --git a/apis/rust/node/src/event_stream/merged.rs b/apis/rust/node/src/event_stream/merged.rs
index df38545ab..b6c0129c8 100644
--- a/apis/rust/node/src/event_stream/merged.rs
+++ b/apis/rust/node/src/event_stream/merged.rs
@@ -1,6 +1,7 @@
 use futures::{Stream, StreamExt};
 use futures_concurrency::stream::Merge;
 
+#[derive(Debug)]
 pub enum MergedEvent<E> {
     Dora(super::Event),
     External(E),