fix lint

Signed-off-by: Jeffrey Kinard <[email protected]>

sdks/python/apache_beam/yaml/yaml_ml.py

@@ -155,7 +155,7 @@ def __init__(
     so that input data can be sent using an API request, and inferences can be
     received as a response.
 
-    This Model Handler also required a `preprocess` function to be defined.
+    This Model Handler also requires a `preprocess` function to be defined.
     Preprocessing and Postprocessing are described in more detail in the
     RunInference docs:
     https://beam.apache.org/releases/yamldoc/current/#runinference
@@ -434,14 +434,13 @@ def fn(x: PredictionResult):
   if missing_params:
     raise ValueError(f'Missing parameters in model_handler: {missing_params}')
   typ = model_handler['type']
-  model_handler_provider = ModelHandlerProvider.handler_types.get(typ, None)
-  if model_handler_provider and issubclass(model_handler_provider,
-                                           type(ModelHandlerProvider)):
-    model_handler_provider.validate(model_handler['config'])
-  else:
+  model_handler_provider_type = ModelHandlerProvider.handler_types.get(
+      typ, None)
+  if not model_handler_provider_type:
     raise NotImplementedError(f'Unknown model handler type: {typ}.')
 
   model_handler_provider = ModelHandlerProvider.create_handler(model_handler)
+  model_handler_provider.validate(model_handler['config'])
   user_type = RowTypeConstraint.from_user_type(pcoll.element_type.user_type)
   schema = RowTypeConstraint.from_fields(
       list(user_type._fields if user_type else []) +