Handling Missing Keys in a Dictionary with Default Values in Python 3.9
I'm building a feature where Can someone help me understand I'm currently working on a Python 3.9 project where I need to aggregate data from a list of dictionaries. Each dictionary represents an item with various properties, but not all items have the same keys. I want to sum values for a specific key, and if a key is missing, I want to treat it as zero. I've tried using the `get()` method to retrieve values, but I'm running into issues when trying to sum them up, especially when dealing with a large number of items. Here's a simplified version of what I'm doing: ```python items = [ {'name': 'item1', 'value': 10}, {'name': 'item2', 'value': 20}, {'name': 'item3'}, # Missing 'value' {'name': 'item4', 'value': 15} ] total_value = 0 for item in items: total_value += item.get('value', 0) # Default to 0 if 'value' is missing print(total_value) # Expected output: 45 ``` This works fine for summing the values, but I noticed that if I try to access other keys (e.g., 'name') during the same iteration, I get a KeyError if the key is missing. I want to avoid adding unnecessary checks for each key I want to access since this could make the code less readable. Is there a better way to handle this situation, perhaps by using a more Pythonic approach or a design pattern? I considered using `collections.defaultdict`, but I'm not entirely sure how it fits into my use case where I'm not just initializing values but also need to sum them up. Any advice or best practices would be appreciated! The project is a service built with Python. How would you solve this? What's the correct way to implement this? For context: I'm using Python on Ubuntu 22.04. Any suggestions would be helpful.