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Collections in Python

Python provides several built-in collection types for storing and organizing data.

List

A mutable, ordered sequence of items. 

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fruits = ["apple", "banana", "cherry"]

Tuple

An immutable, ordered sequence of items. 

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point = (10, 20)

Set

An unordered collection of unique items. 

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unique_numbers = {1, 2, 3, 2}
# {1, 2, 3}

Dictionary

A collection of key-value pairs. 

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person = {"name": "Alice", "age": 30}

The collections Module

The collections module provides additional data structures: - deque: Fast appends and pops from both ends - Counter: Counts hashable objects - defaultdict: Dictionary with default values - OrderedDict: Dictionary that remembers insertion order - namedtuple: Factory for tuple subclasses with named fields

Example

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from collections import Counter
words = ["apple", "banana", "apple"]
count = Counter(words)
print(count)  # Counter({'apple': 2, 'banana': 1})

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