Update app.py

app.py

@@ -16,9 +16,9 @@ def get_data_preview(file):
 
 def label_data(ranges):
     global global_data
-    for start, end, label in ranges:
+    for start, end, label in ranges.values:
         global_data.loc[start:end, 'label'] = label
-    return global_data.head()
+    return global_data.tail()
 
 def preprocess_data():
     global global_data