[Python O11Y] Add _registered_method to __init__.py (#35482 An error occurred )

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Closes #35482
  
An error occurred
 


COPYBARA_INTEGRATE_REVIEW=https://github.com/grpc/grpc/pull/35482 from XuanWang-Amos:fix_registered_method 49321c83b8
PiperOrigin-RevId: 596967469

src/python/grpcio/grpc/__init__.py

@@ -1000,7 +1000,11 @@ class Channel(abc.ABC):
 
     @abc.abstractmethod
     def unary_unary(
-        self, method, request_serializer=None, response_deserializer=None
+        self,
+        method,
+        request_serializer=None,
+        response_deserializer=None,
+        _registered_method=False,
     ):
         """Creates a UnaryUnaryMultiCallable for a unary-unary method.
 
@@ -1011,6 +1015,8 @@ class Channel(abc.ABC):
           response_deserializer: Optional :term:`deserializer` for deserializing the
             response message. Response goes undeserialized in case None
             is passed.
+          _registered_method: Internal Only. A bool representing whether the method
+            is registered.
 
         Returns:
           A UnaryUnaryMultiCallable value for the named unary-unary method.
@@ -1019,7 +1025,11 @@ class Channel(abc.ABC):
 
     @abc.abstractmethod
     def unary_stream(
-        self, method, request_serializer=None, response_deserializer=None
+        self,
+        method,
+        request_serializer=None,
+        response_deserializer=None,
+        _registered_method=False,
     ):
         """Creates a UnaryStreamMultiCallable for a unary-stream method.
 
@@ -1030,6 +1040,8 @@ class Channel(abc.ABC):
           response_deserializer: Optional :term:`deserializer` for deserializing the
             response message. Response goes undeserialized in case None is
             passed.
+          _registered_method: Internal Only. A bool representing whether the method
+            is registered.
 
         Returns:
           A UnaryStreamMultiCallable value for the name unary-stream method.
@@ -1038,7 +1050,11 @@ class Channel(abc.ABC):
 
     @abc.abstractmethod
     def stream_unary(
-        self, method, request_serializer=None, response_deserializer=None
+        self,
+        method,
+        request_serializer=None,
+        response_deserializer=None,
+        _registered_method=False,
     ):
         """Creates a StreamUnaryMultiCallable for a stream-unary method.
 
@@ -1049,6 +1065,8 @@ class Channel(abc.ABC):
           response_deserializer: Optional :term:`deserializer` for deserializing the
             response message. Response goes undeserialized in case None is
             passed.
+          _registered_method: Internal Only. A bool representing whether the method
+            is registered.
 
         Returns:
           A StreamUnaryMultiCallable value for the named stream-unary method.
@@ -1057,7 +1075,11 @@ class Channel(abc.ABC):
 
     @abc.abstractmethod
     def stream_stream(
-        self, method, request_serializer=None, response_deserializer=None
+        self,
+        method,
+        request_serializer=None,
+        response_deserializer=None,
+        _registered_method=False,
     ):
         """Creates a StreamStreamMultiCallable for a stream-stream method.
 
@@ -1068,6 +1090,8 @@ class Channel(abc.ABC):
           response_deserializer: Optional :term:`deserializer` for deserializing the
             response message. Response goes undeserialized in case None
             is passed.
+          _registered_method: Internal Only. A bool representing whether the method
+            is registered.
 
         Returns:
           A StreamStreamMultiCallable value for the named stream-stream method.