Reference library

Dictionaries & sets

Key–value maps, uniqueness, counting, grouping, and fast lookups.

3 matches
Dictionaries & sets easy

Group Data by Key in Python with Dictionaries and Sets

Group items into a dictionary of sets using a key function, a beginner-friendly pattern for organizing data by categories.

grouping dictionaries sets
Python
def group_data(items, key_func):
    """Group items into a dictionary of sets based on a key function."""
    grouped = {}
    for item in items:
        key = key_func(item)
        if key not in grouped:
            grouped[key] = set()
        grouped[key].add(item)
    return grouped


if __name__ == "__main__":
 …
15 0 Open
Dictionaries & sets easy

How to Use Dictionaries and Sets in Python for Beginners

Demonstrates Python dictionary operations and set operations with examples, including access, modification, defaults, and set algebra.

dictionary set beginner
Python
def demonstrate_collections():
    # Dictionary basics
    student = {
        "name": "Alice",
        "age": 20,
        "courses": ["Math", "Physics"]
    }
    print("Dictionary:", student)

    # Access and modify
    student["age"] = 21
    student["grade"] = "A"
    print("Modified:", student)

    # Get with d…
11 0 Open
Dictionaries & sets easy

How to Use Dictionaries and Sets in Python for Beginners

Introduces Python dictionaries and sets with practical examples including creating, modifying, and performing set operations, plus a word-frequency counter.

dictionaries sets data structures
Python
def demonstrate_dict_sets():
    # Create a dictionary with basic info
    person = {
        "name": "Alice",
        "age": 30,
        "city": "New York"
    }
    print("Dictionary:", person)

    # Access and modify dictionary values
    person["age"] = 31
    person["email"] = "alice@example.com"
    print("Afte…
15 0 Open

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Dictionaries & sets — Python code examples

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