resolve issue with double underscore prefix

Author: parthea

packages/gapic-generator/gapic/templates/examples/feature_fragments.j2

@@ -298,7 +298,7 @@ response = {% if transport == "grpc-async" %}await {% endif %}operation.result()
 
 {% macro render_method_name(sample) %}
 {% set name = (sample.client_method_name or sample.rpc)|snake_case %}
-{% if sample.is_internal %}
+{% if sample.is_internal and not name.startswith('_') %}
 _{{ name }}
 {% else %}
 {{ name }}