Improve isoformat timestamp performance for full states (#37105)

homeassistant/components/history/__init__.py

@@ -669,6 +669,33 @@ class LazyState(State):
         """Set last updated datetime."""
         self._last_updated = value
 
+    def as_dict(self):
+        """Return a dict representation of the LazyState.
+
+        Async friendly.
+
+        To be used for JSON serialization.
+        """
+        if self._last_changed:
+            last_changed_isoformat = self._last_changed.isoformat()
+        else:
+            last_changed_isoformat = process_timestamp_to_utc_isoformat(
+                self._row.last_changed
+            )
+        if self._last_updated:
+            last_updated_isoformat = self._last_updated.isoformat()
+        else:
+            last_updated_isoformat = process_timestamp_to_utc_isoformat(
+                self._row.last_updated
+            )
+        return {
+            "entity_id": self.entity_id,
+            "state": self.state,
+            "attributes": self._attributes or self.attributes,
+            "last_changed": last_changed_isoformat,
+            "last_updated": last_updated_isoformat,
+        }
+
     def __eq__(self, other):
         """Return the comparison."""
         return (