diff --git a/libs/langgraph/langgraph/channels/any_value.py b/libs/langgraph/langgraph/channels/any_value.py
index 9539ff8a5..51493ab19 100644
--- a/libs/langgraph/langgraph/channels/any_value.py
+++ b/libs/langgraph/langgraph/channels/any_value.py
@@ -30,7 +30,8 @@ class AnyValue(Generic[Value], BaseChannel[Value, Value, Value]):
         """The type of the update received by the channel."""
         return self.typ
 
-    def copy(self):
+    def copy(self) -> Self:
+        """Return a copy of the channel."""
         empty = self.__class__(self.typ, self.key)
         empty.value = self.value
         return empty
diff --git a/libs/langgraph/langgraph/channels/binop.py b/libs/langgraph/langgraph/channels/binop.py
index b97c4c5fa..1f95d5562 100644
--- a/libs/langgraph/langgraph/channels/binop.py
+++ b/libs/langgraph/langgraph/channels/binop.py
@@ -66,7 +66,8 @@ class BinaryOperatorAggregate(Generic[Value], BaseChannel[Value, Value, Value]):
         """The type of the update received by the channel."""
         return self.typ
 
-    def copy(self):
+    def copy(self) -> Self:
+        """Return a copy of the channel."""
         empty = self.__class__(self.typ, self.operator)
         empty.key = self.key
         empty.value = self.value
diff --git a/libs/langgraph/langgraph/pregel/algo.py b/libs/langgraph/langgraph/pregel/algo.py
index 3e8a3bded..e43890498 100644
--- a/libs/langgraph/langgraph/pregel/algo.py
+++ b/libs/langgraph/langgraph/pregel/algo.py
@@ -192,11 +192,11 @@ def local_read(
         local_channels: dict[str, BaseChannel] = {}
         for k in channels:
             if k in updated:
-                c = channels[k].copy()
-                c.update(updated[k])
+                cc = channels[k].copy()
+                cc.update(updated[k])
             else:
-                c = channels[k]
-            local_channels[k] = c
+                cc = channels[k]
+            local_channels[k] = cc
         # read fresh values
         values = read_channels(local_channels, select)
     else: