def METHOD_NAME(app_name, env_name, var_list, timeout=None):
    options, options_to_remove = create_environment_variables_list(var_list)
    request_id = elasticbeanstalk.update_environment(env_name, options,
                                                     remove=options_to_remove)
    if timeout is None:
        timeout = 4
    commonops.wait_for_success_events(request_id,
                                      timeout_in_minutes=timeout,
                                      can_abort=True)