Set<String> friends = Sets.newHashSet("Tom", "Joe", "Dave");
    Set<String> enemies = Sets.newHashSet("Dick", "Harry", "Tom");

    Set<String> goodFriends = Sets.difference(friends, enemies);
    assertEquals(2, goodFriends.size());

    ImmutableSet<String> immut = Sets.difference(friends, enemies).immutableCopy();
    HashSet<String> mut = Sets.difference(friends, enemies).copyInto(new HashSet<String>());

    id: int
    name: str = "John Doe"
    signup_ts: datetime | None = None
    friends: list[int] = []


external_data = {
    "id": "123",
    "signup_ts": "2017-06-01 12:22",
    "friends": [1, "2", b"3"],
}
user = User(**external_data)
print(user)
# > User id=123 name='John Doe' signup_ts=datetime.datetime(2017, 6, 1, 12, 22) friends=[1, 2, 3]
print(user.id)

		*GetUser("delete_slice_with_associations2", Config{Account: true, Pets: 3, Toys: 2, Company: true, Manager: true, Team: 2, Languages: 2, Friends: 3}),
		*GetUser("delete_slice_with_associations3", Config{Account: true, Pets: 2, Toys: 3, Company: true, Manager: true, Team: 3, Languages: 3, Friends: 2}),

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	CompanyID *int
	Company   *tests.Company
	ManagerID *uint
	Manager   *User
	Team      []*User           `gorm:"foreignkey:ManagerID"`
	Languages []*tests.Language `gorm:"many2many:UserSpeak"`
	Friends   []*User           `gorm:"many2many:user_friends"`
	Active    *bool
}

type (
	mytime time.Time
	myint  int
	mybool = bool
)

type AdvancedDataTypeUser struct {
	ID           sql.NullInt64
	Name         *sql.NullString

# FastAPI and friends newsletter

<iframe data-w-type="embedded" frameborder="0" scrolling="no" marginheight="0" marginwidth="0" src="https://xr4n4.mjt.lu/wgt/xr4n4/hj5/form?c=40a44fa4" width="100%" style="height: 0;"></iframe>

    type: str


class CarItem(BaseItem):
    type: str = "car"


class PlaneItem(BaseItem):
    type: str = "plane"
    size: int


items = {
    "item1": {"description": "All my friends drive a low rider", "type": "car"},
    "item2": {
        "description": "Music is my aeroplane, it's my aeroplane",
        "type": "plane",
        "size": 5,
    },
}

		t.Errorf("failed to create table ccc")
	}

	for _, indexes := range [][2]string{
		{"user_speaks", "fk_user_speaks_user"},
		{"user_speaks", "fk_user_speaks_language"},
		{"user_friends", "fk_user_friends_user"},
		{"user_friends", "fk_user_friends_friends"},
		{"accounts", "fk_users_account"},
		{"users", "fk_users_team"},
		{"users", "fk_users_company"},
	} {
		if !DB.Migrator().HasConstraint(indexes[0], indexes[1]) {

	DB.Create(&user)

	DB.Preload("Team").Preload("Languages").Preload("Friends").First(&user, "name = ?", user.Name)

	if r, err := json.Marshal(&user); err != nil {
		t.Errorf("failed to marshal users, got error %v", err)
	} else if !regexp.MustCompile(`"Team":\[\],"Languages":\[\],"Friends":\[\]`).MatchString(string(r)) {
		t.Errorf("json marshal is not empty slice, got %v", string(r))
	}

{
    "title": "Murder on the Orient Express",
    "authorInfo": {
        "name": "Agatha Christie",
        "yearRange": [1890, 1976],
        "penName": "Mary Westmacott"
    },
    "genre": "Crime novel",
    "publicationHistory": [
        {
            "year": 1934,
            "publisher": "Collins Crime Club (London)",
            "type": "Hardcover",
            "pages": 256
        },
        {
            "year": 1934,