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Dictionaries & sets

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

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How to Extract Data by Category in Python with Dictionaries and Sets

Use set comprehensions and a defaultdict to extract product names by category and compute total prices per category from a list of dictionaries.

dictionaries sets comprehensions
Python 
from collections import defaultdict

# Sample data: products with categories and prices
product_data = [
    {"name": "Apple", "category": "fruit", "price": 0.50},
    {"name": "Banana", "category": "fruit", "price": 0.30},
    {"name": "Carrot", "category": "vegetable", "price": 0.80},
    {"name": "Bread", "category…
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