in source/lambda_handlers/05-CERTrainingCompleteCheck.py [0:0]
def prepend_to_s3_file_name(object_key, prefix="", addRandom=False):
object_key_list = object_key.split('/')
if addRandom:
object_key_list[-1] = prefix + "_" + str(random.randint(10000, 99999)) + "_" + object_key_list[-1]
else:
object_key_list[-1] = prefix + "_" + object_key_list[-1]
return "/".join(object_key_list)