Update return type for Runnable.__or__ (#12880)

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libs/langchain/langchain/schema/runnable/base.py

@@ -258,7 +258,7 @@ class Runnable(Generic[Input, Output], ABC):
             Callable[[Iterator[Any]], Iterator[Other]],
             Mapping[str, Union[Runnable[Any, Other], Callable[[Any], Other], Any]],
         ],
-    ) -> Runnable[Input, Other]:
+    ) -> RunnableSerializable[Input, Other]:
         """Compose this runnable with another object to create a RunnableSequence."""
         return RunnableSequence(first=self, last=coerce_to_runnable(other))
 
@@ -270,7 +270,7 @@ class Runnable(Generic[Input, Output], ABC):
             Callable[[Iterator[Other]], Iterator[Any]],
             Mapping[str, Union[Runnable[Other, Any], Callable[[Other], Any], Any]],
         ],
-    ) -> Runnable[Other, Output]:
+    ) -> RunnableSerializable[Other, Output]:
         """Compose this runnable with another object to create a RunnableSequence."""
         return RunnableSequence(first=coerce_to_runnable(other), last=self)
 
@@ -1162,7 +1162,7 @@ class RunnableSequence(RunnableSerializable[Input, Output]):
             Callable[[Iterator[Any]], Iterator[Other]],
             Mapping[str, Union[Runnable[Any, Other], Callable[[Any], Other], Any]],
         ],
-    ) -> Runnable[Input, Other]:
+    ) -> RunnableSerializable[Input, Other]:
         if isinstance(other, RunnableSequence):
             return RunnableSequence(
                 first=self.first,
@@ -1184,7 +1184,7 @@ class RunnableSequence(RunnableSerializable[Input, Output]):
             Callable[[Iterator[Other]], Iterator[Any]],
             Mapping[str, Union[Runnable[Other, Any], Callable[[Other], Any], Any]],
         ],
-    ) -> Runnable[Other, Output]:
+    ) -> RunnableSerializable[Other, Output]:
         if isinstance(other, RunnableSequence):
             return RunnableSequence(
                 first=other.first,