Reference library

Dictionaries & sets

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

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Dictionaries & sets easy

Build an OrderedDict insertion order demo in Python 3

Demonstrate how OrderedDict preserves insertion order, how updates keep position, and how re-insertion moves keys to the end.

ordereddict dictionaries insertion-order
Python 
from collections import OrderedDict

def demo_ordered_dict():
    # Create an OrderedDict and insert items in a specific order
    ordered = OrderedDict()
    ordered['banana'] = 3
    ordered['apple'] = 2
    ordered['cherry'] = 5
    ordered['date'] = 1

    print("Insertion order preserved:")
    for key, value in …
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