Python add set item

In Python, you can add elements to a set using the add() and update() methods.

Adding a Single Element with add()

The add() method adds a single element to the set. If the element is already in the set, it won’t be added again, as sets only contain unique items.


data_set = {1, 2, 3, 4, 5}
data_set.add(6)  # Adds 6 to the set
print(data_set)  # Output: {1, 2, 3, 4, 5, 6}

data_set.add(2)  # Adding a duplicate value; nothing changes
print(data_set)  # Output: {1, 2, 3, 4, 5, 6}

Example2:


# Initialize a set
fruits = {"apple", "banana"}

# Add a single element
fruits.add("orange")
print(fruits)  # Output: {"apple", "banana", "orange"}

Adding Multiple Elements with update()

To add multiple elements at once, use the update() method. You can pass any iterable (like a list, tuple, or another set), and all unique items from that iterable will be added to the set.


data_set = {1, 2, 3, 4, 5}
data_set.update([6, 7, 8])  # Adds 6, 7, and 8 to the set
print(data_set)  # Output: {1, 2, 3, 4, 5, 6, 7, 8}

# Adding elements from another set
data_set.update({7, 8, 9})
print(data_set)  # Output: {1, 2, 3, 4, 5, 6, 7, 8, 9}

# Adding elements from a string (unique characters will be added)
my_set.update("hello")
print(data_set)  # Output may include {1, 2, 3, 4, 5, 6, 7, 8, 9, 'h', 'e', 'l', 'o'}

Example2:


# Initialize a set
fruits = {"apple", "banana"}

# Add multiple elements
fruits.update(["mango", "orange"])
print(fruits)  # Output: {"apple", "banana", "mango", "orange"}