improved comments

Author: daniel-sanche

google/cloud/bigtable/data/_async/metrics_interceptor.py

@@ -134,6 +134,7 @@ async def intercept_unary_stream(
                 operation, await continuation(client_call_details, request)
             )
         except Exception as rpc_error:
+            # handle errors while intializing stream
             metadata = await _get_metadata(rpc_error)
             if metadata is not None:
                 operation.add_response_metadata(metadata)
@@ -143,7 +144,7 @@ async def intercept_unary_stream(
     @CrossSync.convert
     async def _streaming_generator_wrapper(operation, call):
         """
-        Wrapped generator to be returned by intercept_unary_stream
+        Wrapped generator to be returned by intercept_unary_stream.
         """
         # only track has_first response for READ_ROWS
         has_first_response = (

google/cloud/bigtable/data/_sync_autogen/metrics_interceptor.py

@@ -102,7 +102,7 @@ def intercept_unary_stream(
 
     @staticmethod
     def _streaming_generator_wrapper(operation, call):
-        """Wrapped generator to be returned by intercept_unary_stream"""
+        """Wrapped generator to be returned by intercept_unary_stream."""
         has_first_response = (
             operation.first_response_latency_ns is not None
             or operation.op_type != OperationType.READ_ROWS