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Checking if a given key already exists in a dictionary in Python

Programming
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Python
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Operations
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Dictionary Operations
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Cookbooks
schedule Jul 1, 2022
Last updated
local_offer Python
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tocTable of Contents
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We can check if a key already exists in a dictionary by using the operator in.

Example

To check if key2 already exists as a key in dictionary d:

d = {'key1': 1, 'key2': 2, 'key3': 3}

if 'key2' in d:
   print("Exists")

else:
   print("Doesn't Exist")
Exists

The above if-else block is based on the fact that comparison using the in operator returns a boolean:

d = {'key1': 1, 'key2': 2, 'key3': 3}

'key2' in d
True
robocat
Published by Isshin Inada
Edited by 0 others
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