Add Prefix to Each Key Name in Dictionary - Python Last Updated : 25 Jan, 2025 Comments Improve Suggest changes Like Article Like Report Adding a prefix to each key in a dictionary is a common task when manipulating or organizing data. For example, we might want to indicate the source of the keys or make them more descriptive. Let's explore multiple methods to achieve this in Python.Using Dictionary ComprehensionWe can use dictionary comprehension to efficiently add a prefix to each key in the dictionary. Python # Initialize a dictionary a = {"name": "Nikki", "age": 25, "city": "New York"} # Add prefix to each key b = {f"prefix_{k}": v for k, v in a.items()} # Print the updated dictionary print(b) Output{'prefix_name': 'Nikki', 'prefix_age': 25, 'prefix_city': 'New York'} Explanation:The dictionary comprehension loops over the key-value pairs using a.items().For each key k, the prefix "prefix_" is added using an f-string.The result is a new dictionary with updated keys and the original values.Let's explore some more ways and see how we can add prefix to each key name in dictionary.Using map() for keysmap() function can be used with a lambda function to apply a transformation to the keys. Python # Initialize a dictionary a = {"name": "Nikki", "age": 25, "city": "New York"} # Add prefix to each key b = dict(map(lambda x: (f"prefix_{x[0]}", x[1]), a.items())) # Print the updated dictionary print(b) Output{'prefix_name': 'Nikki', 'prefix_age': 25, 'prefix_city': 'New York'} Explanation:map() function applies the lambda function to each key-value pair in a.items().lambda function modifies the key by adding the prefix while keeping the value unchanged.dict() function is used to convert the mapped items back into a dictionary.Using for LoopA traditional for loop can also be used to create a new dictionary with prefixed keys. Python # Initialize a dictionary a = {"name": "Nikki", "age": 25, "city": "New York"} # Initialize an empty dictionary b = {} # Add prefix to each key for k, v in a.items(): b[f"prefix_{k}"] = v # Print the updated dictionary print(b) Output{'prefix_name': 'Nikki', 'prefix_age': 25, 'prefix_city': 'New York'} Explanation:An empty dictionary b is initialized to store the new key-value pairs.The for loop iterates over a.items(), and the prefix is added to each key using an f-string.Each updated key-value pair is added to the new dictionary. Comment More infoAdvertise with us Next Article Add Prefix to Each Key Name in Dictionary - Python manjeet_04 Follow Improve Article Tags : Python Python Programs Python dictionary-programs Practice Tags : python Similar Reads How to Print Dictionary Keys in Python We are given a dictionary and our task is to print its keys, this can be helpful when we want to access or display only the key part of each key-value pair. 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