|  | @@ -55,15 +55,15 @@ _INITIAL_METADATA_FOR_GENERIC_HANDLER = aio.Metadata(
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				|  |  |  _INVALID_METADATA_TEST_CASES = (
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				|  |  |      (
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				|  |  |          TypeError,
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				|  |  | -        aio.Metadata((42, 42),),
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				|  |  | +        ((42, 42),),
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				|  |  |      ),
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				|  |  |      (
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				|  |  |          TypeError,
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				|  |  | -        aio.Metadata(({}, {}),),
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				|  |  | +        ((None, {}),),
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				|  |  |      ),
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				|  |  |      (
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				|  |  |          TypeError,
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				|  |  | -        aio.Metadata(('normal', object()),),
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				|  |  | +        (('normal', object()),),
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				|  |  |      ),
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				|  |  |  )
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				|  |  |  
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				|  | @@ -100,13 +100,13 @@ class _TestGenericHandlerForMethods(grpc.GenericRpcHandler):
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				|  |  |      async def _test_server_to_client(request, context):
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				|  |  |          assert _REQUEST == request
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				|  |  |          await context.send_initial_metadata(
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				|  |  | -            _INITIAL_METADATA_FROM_SERVER_TO_CLIENT)
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				|  |  | +            tuple(_INITIAL_METADATA_FROM_SERVER_TO_CLIENT))
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				|  |  |          return _RESPONSE
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				|  |  |  
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				|  |  |      @staticmethod
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				|  |  |      async def _test_trailing_metadata(request, context):
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				|  |  |          assert _REQUEST == request
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				|  |  | -        context.set_trailing_metadata(_TRAILING_METADATA)
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				|  |  | +        context.set_trailing_metadata(tuple(_TRAILING_METADATA))
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				|  |  |          return _RESPONSE
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				|  |  |  
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				|  |  |      @staticmethod
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				|  | @@ -115,21 +115,21 @@ class _TestGenericHandlerForMethods(grpc.GenericRpcHandler):
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				|  |  |          assert _common.seen_metadata(_INITIAL_METADATA_FROM_CLIENT_TO_SERVER,
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				|  |  |                                       context.invocation_metadata())
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				|  |  |          await context.send_initial_metadata(
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				|  |  | -            _INITIAL_METADATA_FROM_SERVER_TO_CLIENT)
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				|  |  | +            tuple(_INITIAL_METADATA_FROM_SERVER_TO_CLIENT))
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				|  |  |          yield _RESPONSE
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				|  |  | -        context.set_trailing_metadata(_TRAILING_METADATA)
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				|  |  | +        context.set_trailing_metadata(tuple(_TRAILING_METADATA))
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				|  |  |  
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				|  |  |      @staticmethod
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				|  |  |      async def _test_stream_unary(request_iterator, context):
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				|  |  |          assert _common.seen_metadata(_INITIAL_METADATA_FROM_CLIENT_TO_SERVER,
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				|  |  |                                       context.invocation_metadata())
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				|  |  |          await context.send_initial_metadata(
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				|  |  | -            _INITIAL_METADATA_FROM_SERVER_TO_CLIENT)
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				|  |  | +            tuple(_INITIAL_METADATA_FROM_SERVER_TO_CLIENT))
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				|  |  |  
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				|  |  |          async for request in request_iterator:
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				|  |  |              assert _REQUEST == request
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				|  |  |  
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				|  |  | -        context.set_trailing_metadata(_TRAILING_METADATA)
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				|  |  | +        context.set_trailing_metadata(tuple(_TRAILING_METADATA))
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				|  |  |          return _RESPONSE
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				|  |  |  
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				|  |  |      @staticmethod
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				|  | @@ -137,13 +137,13 @@ class _TestGenericHandlerForMethods(grpc.GenericRpcHandler):
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				|  |  |          assert _common.seen_metadata(_INITIAL_METADATA_FROM_CLIENT_TO_SERVER,
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				|  |  |                                       context.invocation_metadata())
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				|  |  |          await context.send_initial_metadata(
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				|  |  | -            _INITIAL_METADATA_FROM_SERVER_TO_CLIENT)
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				|  |  | +            tuple(_INITIAL_METADATA_FROM_SERVER_TO_CLIENT))
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				|  |  |  
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				|  |  |          async for request in request_iterator:
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				|  |  |              assert _REQUEST == request
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				|  |  |  
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				|  |  |          yield _RESPONSE
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				|  |  | -        context.set_trailing_metadata(_TRAILING_METADATA)
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				|  |  | +        context.set_trailing_metadata(tuple(_TRAILING_METADATA))
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				|  |  |  
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				|  |  |      def service(self, handler_call_details):
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				|  |  |          return self._routing_table.get(handler_call_details.method)
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				|  | @@ -193,6 +193,7 @@ class TestMetadata(AioTestBase):
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				|  |  |      async def test_from_server_to_client(self):
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				|  |  |          multicallable = self._client.unary_unary(_TEST_SERVER_TO_CLIENT)
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				|  |  |          call = multicallable(_REQUEST)
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				|  |  | +
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				|  |  |          self.assertEqual(_INITIAL_METADATA_FROM_SERVER_TO_CLIENT, await
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				|  |  |                           call.initial_metadata())
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				|  |  |          self.assertEqual(_RESPONSE, await call)
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				|  | @@ -207,8 +208,8 @@ class TestMetadata(AioTestBase):
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				|  |  |  
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				|  |  |      async def test_from_client_to_server_with_list(self):
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				|  |  |          multicallable = self._client.unary_unary(_TEST_CLIENT_TO_SERVER)
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				|  |  | -        call = multicallable(
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				|  |  | -            _REQUEST, metadata=list(_INITIAL_METADATA_FROM_CLIENT_TO_SERVER))
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				|  |  | +        call = multicallable(_REQUEST,
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				|  |  | +                             metadata=_INITIAL_METADATA_FROM_CLIENT_TO_SERVER)
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				|  |  |          self.assertEqual(_RESPONSE, await call)
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				|  |  |          self.assertEqual(grpc.StatusCode.OK, await call.code())
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				|  |  |  
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