KeyError in Dictionaries

Understanding KeyError in Python Dictionaries

Introduction:

A KeyError in Python occurs when you try to access a key that doesn’t exist in a dictionary. This can happen due to typos or if the key was never added. Understanding how to handle KeyErrors is crucial for effective error management in your code. Let’s look at common causes and prevention strategies.

Preventing and Handling KeyError in Dictionaries

The Problem:

A KeyError occurs when you try to access a key that doesn’t exist in a Python dictionary:

my_dict = {“name”: “John”, “age”: 30}
print(my_dict[“address”]) # KeyError: ‘address’

The Solution:

You can use the .get() method to handle missing keys more gracefully:

print(my_dict.get(“address”, “Address not available”)) # Output: Address not available

This avoids throwing an error and returns a default value if the key is not found.