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Data pipelines & processing

ETL-style flows, batch transforms, validation, and moving data between formats.

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Data pipelines & processing easy

How to Group Data by Key in Python

Group a list of dictionaries by a specified key using a defaultdict and compute per-group averages.

grouping defaultdict data-pipelines
Python 
from collections import defaultdict

def group_by_key(data, key):
    grouped = defaultdict(list)
    for item in data:
        grouped[item[key]].append(item)
    return dict(grouped)

if __name__ == "__main__":
    records = [
        {"name": "Alice", "dept": "Engineering", "score": 85},
        {"name": "Bob", "de…
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