How to Rename Dictionary Keys in Python: Two Efficient Methods

Renaming Dictionary Keys: Simple and Efficient Solutions

Python dictionaries are ubiquitous for organizing data structures, but occasionally you may need to change the name of a key. While this task may seem trivial, there are several ways to approach it effectively.

Two-Step Method:

This approach involves creating a new key and assigning the value associated with the old key to it. Subsequently, the old key is removed from the dictionary. Here's how it works:

dictionary[new_key] = dictionary[old_key]
del dictionary[old_key]

Single-Step Method:

For a more concise solution, you can use the pop() method to both retrieve the value associated with the old key and remove it from the dictionary. The syntax is:

dictionary[new_key] = dictionary.pop(old_key)

However, this method raises a KeyError if the old key is not present in the dictionary.

Additional Notes:

Note: The pop() method will delete the original key once the value is assigned to the new key.

Example:

Consider a dictionary dictionary = { 1: 'one', 2:'two', 3:'three' }.

Using the one-step method:

dictionary['ONE'] = dictionary.pop(1)

Will result in:

{2: 'two', 3: 'three', 'ONE': 'one'}

Conversely, if you attempt to use the same method with a non-existent key, a KeyError will be raised.

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