How to use the iotedgedev.output.Output function in iotedgedev

def utility():
    output = Output()
    envvars = EnvVars(output)
    envvars.load()
    return Utility(envvars, output)

def test_in_command_list_empty_3():
    output = Output()
    envvars = EnvVars(output)
    assert envvars.in_command_list("", ["init", "e2e", "", "new", "simulator stop"])

def setup_test_env(request):
    output = Output()
    envvars = EnvVars(output)
    envvars.set_envvar("CONTAINER_REGISTRY_SERVER_UNITTEST", 'unittest.azurecr.io')
    envvars.set_envvar("CONTAINER_REGISTRY_USERNAME_UNITTEST", 'username')
    envvars.set_envvar("CONTAINER_REGISTRY_PASSWORD_UNITTEST", 'password')

    def clean():
        os.environ.pop("CONTAINER_REGISTRY_SERVER_UNITTEST")
        os.environ.pop("CONTAINER_REGISTRY_USERNAME_UNITTEST")
        os.environ.pop("CONTAINER_REGISTRY_PASSWORD_UNITTEST")
    request.addfinalizer(clean)

    return

def test_is_terse_command_empty():
    output = Output()
    envvars = EnvVars(output)
    assert envvars.is_terse_command("")

def test_default_container_registry_server_key_exists():
    output = Output()
    envvars = EnvVars(output)
    envvars.load()
    assert "CONTAINER_REGISTRY_SERVER" in os.environ

def test_default_container_registry_username_value_exists_or_returns_empty_string():
    output = Output()
    envvars = EnvVars(output)
    username = envvars.get_envvar("CONTAINER_REGISTRY_USERNAME")
    assert username is not None

def test_is_terse_command_false():
    output = Output()
    envvars = EnvVars(output)
    assert not envvars.is_terse_command("solution add")

def test_default_container_registry_server_value_exists():
    output = Output()
    envvars = EnvVars(output)
    server = envvars.get_envvar("CONTAINER_REGISTRY_SERVER")
    assert server is not None

def test_set_envvar():
    output = Output()
    envvars = EnvVars(output)
    registry_server = envvars.get_envvar("DEPLOYMENT_CONFIG_TEMPLATE_FILE")
    envvars.set_envvar("DEPLOYMENT_CONFIG_TEMPLATE_FILE", "deployment.template_new.json")
    new_registry_server = envvars.get_envvar("DEPLOYMENT_CONFIG_TEMPLATE_FILE")
    assert new_registry_server == "deployment.template_new.json"
    envvars.set_envvar("DEPLOYMENT_CONFIG_TEMPLATE_FILE", registry_server)

def __init__(self, build_options):
        self.build_options = build_options
        self.output = Output()
        self.sdk_options = {}