How to remove a key from a dictionary in Python?"

General Discussions
1

How do I delete an item from a dictionary in Python?

Without modifying the original dictionary, how do I obtain another dict with the item removed using Python remove from dictionary?

2

Hello @isha.tantia

Here is the Answer to the Question:-

You can solve this efficiently using dictionary comprehension. It’s a clean and Pythonic way to create a new dictionary while excluding the key you want to remove. Here’s how:

original_dict = {'a': 1, 'b': 2, 'c': 3}  
key_to_remove = 'b'  
new_dict = {k: v for k, v in original_dict.items() if k != key_to_remove}  
print(new_dict)  # Output: {'a': 1, 'c': 3}

This approach is concise and maintains readability, especially for small to medium-sized dictionaries. What do you think?

3

Hey All!

Great suggestion! Dictionary comprehension is indeed elegant. However, if someone prefers working with a shallow copy of the original dictionary, the copy() method combined with pop() could be an alternative.

Here’s how you can do it:

original_dict = {'a': 1, 'b': 2, 'c': 3}  
key_to_remove = 'b'  
new_dict = original_dict.copy()  
new_dict.pop(key_to_remove, None)  
print(new_dict)  # Output: {'a': 1, 'c': 3}

This way, you don’t modify the original dictionary directly, and the use of pop() makes it explicit that you’re removing a key. Thoughts on this approach?"

4

Both approaches are great! Another way to achieve this, especially if you’re a fan of the functional programming style, is by using the dict() constructor along with filtering. Here’s an example:

original_dict = {'a': 1, 'b': 2, 'c': 3}  
key_to_remove = 'b'  
new_dict = dict((k, v) for k, v in original_dict.items() if k != key_to_remove)  
print(new_dict)  # Output: {'a': 1, 'c': 3}

This method is flexible and mirrors the logic of dictionary comprehension while explicitly using the dict() constructor. It might appeal to those who are transitioning from other programming paradigms.