Reference library

Dictionaries & sets

Key–value maps, uniqueness, counting, grouping, and fast lookups.

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Dictionaries & sets easy

How to Validate Required Dict Keys in Python

Check whether a dictionary contains all required keys and return the list of missing ones using a simple list comprehension.

dictionary validation missing-keys
Python 
def find_missing_keys(data: dict, required_keys: list) -> list:
    """Return a list of required keys that are missing from the dictionary."""
    return [key for key in required_keys if key not in data]


if __name__ == "__main__":
    user_data = {
        "name": "Alice",
        "email": "alice@example.com",
     …
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