Reference library

Dictionaries & sets

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

3 matches

How to Validate Text and Count Words in Python

Count word frequencies, find unique and repeated words in a text using Python dictionaries and sets for beginner text validation.

dictionaries sets text-processing

Python

def validate_text(text):
    words = text.lower().split()
    
    word_counts = {}
    for word in words:
        cleaned = word.strip('.,!?;:"\'')
        if cleaned:
            word_counts[cleaned] = word_counts.get(cleaned, 0) + 1
    
    unique_words = set(word_counts.keys())
    repeated_words = {word for word…

12 0 Open

Dictionaries & sets easy

How to swap dict keys and values in Python when values are unique

Swap dict keys and values using a dict comprehension, with a guard that raises an error when values repeat.

dictionary comprehension keys-values

Python

def swap_dict_keys_values(d):
    """Swap keys and values in a dict, assuming values are unique."""
    if len(set(d.values())) != len(d.values()):
        raise ValueError("Values must be unique to swap keys and values")
    return {v: k for k, v in d.items()}

if __name__ == "__main__":
    original = {"a": 1, "b": …

14 0 Open

Dictionaries & sets easy

Multiset with Counter update and elements in Python

Demonstrates using collections.Counter as a multiset: updating counts with update() and iterating elements() to get repeated items.

counter multiset collections

Python

from collections import Counter

multiset = Counter(['apple', 'banana', 'apple'])

multiset.update(['banana', 'cherry', 'apple'])

print("Elements after update:", sorted(multiset.elements()))
print("Counts:", dict(multiset))
print("Most common:", multiset.most_common(2))

13 0 Open

Browse by section

Each section groups closely related Python snippets.