👀 Views: 26 💬 Answers: 1 📅 Created: 2025-07-24

python dictionary nested-dictionary error-handling Python

I'm learning this framework and I'm working through a tutorial and I'm refactoring my project and Quick question that's been bugging me - I'm currently working on a project where I need to update values in a deeply nested dictionary....... The structure of the dictionary can vary, and sometimes keys might not exist, leading to KeyErrors when I try to access them directly. For instance, I have the following dictionary: ```python data = { 'user1': { 'preferences': { 'theme': 'dark' } }, 'user2': { 'preferences': {} } } ``` I want to update the 'theme' key for both users. However, when trying to access `data['user2']['preferences']['theme']`, I get a KeyError because 'theme' doesn't exist yet. I attempted to use the `setdefault` method, but it seems cumbersome: ```python data['user2']['preferences'].setdefault('theme', 'light') ``` This works for setting a default value, but I still face issues when I want to update a value instead of just setting it. I've also tried using a try-except block, but that feels like a hack rather than a clean solution. Is there a more elegant way to handle this situation, especially if the key may not exist at multiple levels? I’m looking for a way to ensure that I can safely update or create keys without hitting a KeyError. Can I use any libraries or built-in functions to simplify this process? This is part of a larger service I'm building. I'm working with Python in a Docker container on Linux. I'd love to hear your thoughts on this. This is part of a larger web app I'm building. Could someone point me to the right documentation?