PythonPractice/Collection Module - defaultdict.py at master · uzairiqbal91/PythonPractice · GitHub

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#!/usr/bin/env python
# coding: utf-8

# # Collection Module
#

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# default dict
# default dict provides all method that comes from a dictionary but also takes first arguement as a default datatype
# defaultdict never raise a keyerror any key that does not exist get the value return by default factory


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from collections import defaultdict


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# simple dict
d = {'k1' : 1}


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# when use d['k2'] it will throw key error
d['k1']


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d = defaultdict(object)


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# it will not throw an error
d['one']


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# we can also use this by default values use that conjuction using lambda functions

d = defaultdict(lambda : 0)


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# it will reutn 0 when their is not key
d['one']


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d['two'] = 2


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d


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# it will automatically assign key pair values with default value when try to the key which is not in dict


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