def generate_test_environment_name(env_name):
    """
    Some environments, like proto, need a numerical index, while others, like
    prod do not.  Given an environment name from the service registry, return a
    valid environment name in which to generate a template.
    """
    if env_name in ['alpha', 'proto']:
        return '{}0'.format(env_name)
    return env_name