KeyError — Easy Examples

Raised when a dictionary key is not found

EasyIntermediateAdvancedExpert

Triggering KeyError

How KeyError is raised and how to catch it.

python
# Triggering and catching KeyError
try:
    d = {}; d["missing"]
except KeyError as e:
    print(f"Caught KeyError: {e}")
    print(f"Type: {type(e).__name__}")

KeyError is raised when raised when a dictionary key is not found. Always catch specific exceptions rather than bare except clauses.

Handling KeyError

Basic error handling pattern for KeyError.

python
# Safe handling pattern
def safe_operation():
    try:
        d = {}; d["missing"]
    except KeyError:
        print("Operation failed gracefully")
        return None

result = safe_operation()
print(f"Result: {result}")

Wrapping risky operations in try/except blocks prevents your program from crashing.

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