Update demo.py

demo.py

@@ -62,6 +62,7 @@ def compare_face(frame1, frame2):
             image1 = Image.open(frame1)
             image2 = Image.open(frame2)
 
+            html = ""
             faces1 = json_result.get("faces1", {})           
             faces2 = json_result.get("faces2", {})
             results = json_result.get("results", {})