in opentelemetry-resourcedetector-gcp/src/opentelemetry/resourcedetector/gcp_resource_detector/_gae.py [0:0]
def service_name() -> str:
"""The service name of the app engine service.
Check that ``on_app_engine()`` is true before calling this, or it may throw exceptions.
"""
return os.environ[_GAE_SERVICE_ENV]