What

OrderedDict is a dictionary subclass that remembers the order that keys were first inserted. dict vs OrderedDict OrderedDict preserves order in which keys are inserted. reguar dict does not track the insertion order.

from collections import OrderedDict 

d = {} 
d['a'] = 1
d['b'] = 2
d['c'] = 3
d['d'] = 4
    
for key, value in d.items(): 
    print(key, value)              #('a', 1) ('c', 3) ('b', 2) ('d', 4)   //See no order
    
od = OrderedDict() 
od['a'] = 1
od['b'] = 2
od['c'] = 3
od['d'] = 4
    
for key, value in od.items(): 
    print(key, value)             #('a', 1) ('b', 2) ('c', 3) ('d', 4)    //See order