11. Sanitizing and Normalizing Input Data

Validation checks correctness; sanitization ensures cleanliness. Normalize input to prevent bypasses through encodings or tricks.

Example

import unicodedata

def clean_input(text):
    normalized = unicodedata.normalize("NFKC", text)
    sanitized = normalized.strip().replace("..", "")
    return sanitized

print(clean_input(" Café ../config"))

✅ Lesson: Normalize, trim, and sanitize inputs before any sensitive operation.