Reference library

Dictionaries & sets

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

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Dictionaries & sets easy

How to Index a List of Records by Unique ID in Python

Build a dictionary that maps each record's unique id to the record itself from a list of dictionaries.

dictionary index records
Python 
from typing import List, Dict, Any

def index_by_id(records: List[Dict[str, Any]], id_field: str = "id") -> Dict[Any, Dict[str, Any]]:
    """Build a dictionary mapping each record's unique id to the record itself."""
    return {record[id_field]: record for record in records}

if __name__ == "__main__":
    sample_re…
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