Dictionary Methods and Nesting

Dictionaries in Python become especially powerful when you use built-in methods and nesting structures.

These techniques help you organize, update, and safely access complex data, which is a key skill in data analysis.

Dictionary methods allow you to interact with data more efficiently:

• .get() retrieves a value safely, even if the key does not exist.
• .update() adds or modifies key-value pairs.
• .pop() removes entries without needing to access them directly.

Using these methods can reduce errors and make your code easier to read.

Nesting means placing one data structure inside another, such as a dictionary inside another dictionary.

This is useful for representing complex or grouped information, for example storing multiple subjects and scores for each student.

Below is an example of a nested dictionary:

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# Create a nested dictionary for a student
student = {
    "name": "Alina",
    "grades": {
        "math": 88,
        "history": 92
    }
}

# Safely access a nested value
math_score = student["grades"].get("math", 0)
print("Math Score:", math_score)  # Output: 88

The student dictionary contains another dictionary inside the grades key.

The .get("math", 0) method looks for the "math" score.

• If it exists, it returns the score (88).
• If it does not, it returns the default value 0 instead of causing an error.

This approach is especially helpful when you work with real-world data that may be incomplete.