Learn about List, Tuples, Sets, Dictionaries in Python

1. Lists

A list is a collection of items that are ordered and changeable. Lists allow duplicate members.

my_list = [1, 2, 3, 4, 5]
print(my_list)  # Output: [1, 2, 3, 4, 5]
my_list.append(6)  # Adding an element
print(my_list)  # Output: [1, 2, 3, 4, 5, 6]

Properties of Lists:

• Ordered: Items have a defined order.
• Mutable: Items can be changed.
• Allows duplicates: Multiple items can have the same value.

2. Tuples

A tuple is similar to a list, but it is immutable. Once a tuple is created, you cannot change its values.

my_tuple = (1, 2, 3, 4, 5)
print(my_tuple)  # Output: (1, 2, 3, 4, 5)
# my_tuple[0] = 10  # This will raise a TypeError

Properties of Tuples:

• Ordered: Items have a defined order.
• Immutable: Items cannot be changed.
• Allows duplicates: Multiple items can have the same value.

3. Dictionaries

A dictionary is a collection of key-value pairs. Dictionaries are unordered, changeable, and do not allow duplicate keys.

my_dict = {"name": "Alice", "age": 25}
print(my_dict)  # Output: {'name': 'Alice', 'age': 25}
my_dict["age"] = 30  # Changing a value
print(my_dict)  # Output: {'name': 'Alice', 'age': 30}

Properties of Dictionaries:

• Unordered: Items do not have a defined order.
• Mutable: Items can be changed.
• No duplicate keys: Each key must be unique.

4. Sets

A set is an unordered collection of unique items. Sets are mutable, but they cannot contain duplicate elements.

my_set = {1, 2, 3, 4, 5}
print(my_set)  # Output: {1, 2, 3, 4, 5}
my_set.add(6)  # Adding an element
print(my_set)  # Output: {1, 2, 3, 4, 5, 6}
my_set.add(3)  # Adding a duplicate will not change the set
print(my_set)  # Output: {1, 2, 3, 4, 5, 6}

Properties of Sets:

• Unordered: Items do not have a defined order.
• Mutable: Items can be changed.
• No duplicate elements: Each item must be unique.

Comparison of Lists, Tuples, Dictionaries, and Sets

Property	List	Tuple	Dictionary	Set
Ordered	Yes	Yes	No	No
Mutable	Yes	No	Yes	Yes
Duplicates	Yes	Yes	No (keys)	No
Access	By index	By index	By key	By value

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