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Adding new key-value pairs to a dictionary Changing values in a dictionary Checking if a dictionary is empty Checking if a given key already exists in a dictionary Looping through key-value pairs in a dictionary Looping through keys in a dictionary Looping through values in a dictionary Merging two dictionaries Removing key-value pairs from a dictionary Retrieving values in a dictionary Sorting a dictionary by value

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

Programming

Python

Operations

Dictionary Operations

Cookbooks

Jul 1, 2022

Last updated

local_offer Python

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

Published by Isshin Inada

Edited by 0 others

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