diff --git a/faker/providers/address/en_IN/__init__.py b/faker/providers/address/en_IN/__init__.py
index 2c51a54d4c..4004bcb4a7 100644
--- a/faker/providers/address/en_IN/__init__.py
+++ b/faker/providers/address/en_IN/__init__.py
@@ -535,7 +535,7 @@ def pincode_in_state(self, state_abbr: Optional[str] = None, include_union_terri
         if state_abbr in known_abbrs:
             codes = self.state_pincode
             if include_union_territories:
-                codes = codes | self.union_territories_pincode
+                codes.update(self.union_territories_pincode)
 
             pincode_range = self.random_element(codes[state_abbr])