exclude coverage calculations on some exceptional lines

Author: vchudnov-g

google/api_core/operations_v1/__init__.py

@@ -33,7 +33,7 @@
     from google.api_core.operations_v1.operations_rest_client_async import AsyncOperationsRestClient
 
     __all__ += ["AsyncOperationsRestClient", "AsyncOperationsRestTransport"]
-except ImportError:
+except ImportError:  # pragma: NO COVER
     # This import requires the `async_rest` extra.
     # Don't raise an exception if `AsyncOperationsRestTransport` cannot be imported
     # as other transports are still available.

google/api_core/operations_v1/abstract_operations_base_client.py

@@ -32,7 +32,7 @@
     )
 
     HAS_ASYNC_REST_DEPENDENCIES = True
-except ImportError as e:
+except ImportError as e:  # pragma: NO COVER
     HAS_ASYNC_REST_DEPENDENCIES = False
     ASYNC_REST_EXCEPTION = e
 
@@ -51,7 +51,7 @@ class AbstractOperationsBaseClientMeta(type):
 
     _transport_registry = OrderedDict()  # type: Dict[str, Type[OperationsTransport]]
     _transport_registry["rest"] = OperationsRestTransport
-    if HAS_ASYNC_REST_DEPENDENCIES:
+    if HAS_ASYNC_REST_DEPENDENCIES:  # pragma: NO COVER
         _transport_registry["rest_asyncio"] = AsyncOperationsRestTransport
 
     def get_transport_class(

google/api_core/operations_v1/transports/__init__.py

@@ -32,7 +32,7 @@
     _transport_registry["rest_asyncio"] = cast(
         OperationsTransport, AsyncOperationsRestTransport
     )
-except ImportError:
+except ImportError:  # pragma: NO COVER
     # This import requires the `async_rest` extra.
     # Don't raise an exception if `AsyncOperationsRestTransport` cannot be imported
     # as other transports are still available.

tests/asyncio/test_rest_streaming_async.py

@@ -33,7 +33,7 @@
 
 try:
     from google.auth.aio.transport import Response
-except ImportError:
+except ImportError:  # pragma: NO COVER
     pytest.skip(
         "google-api-core[async_rest] is required to test asynchronous rest streaming.",
         allow_module_level=True,