I can save and load Datagrid content

src/app.py

@@ -1,6 +1,9 @@
+import json
 import logging.config
 
+import pandas as pd
 import yaml
+from dbengine.handlers import BaseRefHandler, handlers
 from fasthtml import serve
 from fasthtml.components import Div
 
@@ -35,6 +38,23 @@ app, rt = create_app(protect_routes=True,
                      base_url="http://localhost:5003")
 
 
+class DataFrameHandler(BaseRefHandler):
+  def is_eligible_for(self, obj):
+    return isinstance(obj, pd.DataFrame)
+  
+  def tag(self):
+    return "DataFrame"
+  
+  def serialize_to_bytes(self, df) -> bytes:
+    from io import BytesIO
+    import pickle
+    return pickle.dumps(df)
+
+  def deserialize_from_bytes(self, data: bytes):
+    import pickle
+    return pickle.loads(data)
+
+
 def create_sample_treeview(parent):
   """
   Create a sample TreeView with a file structure for testing.
@@ -83,7 +103,9 @@ def create_sample_treeview(parent):
 
 @rt("/")
 def index(session):
-  session_instance = UniqueInstance(session=session, _id=Ids.UserSession)
+  session_instance = UniqueInstance(session=session,
+                                    _id=Ids.UserSession,
+                                    on_init=lambda: handlers.register_handler(DataFrameHandler()))
   layout = Layout(session_instance, "Testing Layout")
   layout.footer_left.add("Goodbye World")