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Errors & debugging

Handle failures gracefully, raise helpful errors, and debug with confidence.

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Errors & debugging medium

Redact secrets from log message formatter in Python

Build a custom logging.Formatter that masks passwords, API keys, and credit card numbers in log output.

logging redaction security
Python 
import re
import logging

class RedactingFormatter(logging.Formatter):
    """Formatter that masks sensitive data in log messages."""
    
    SENSITIVE_PATTERNS = [
        (re.compile(r'password[=:]\s*\S+', re.IGNORECASE), 'password=[REDACTED]'),
        (re.compile(r'api[_-]?key[=:]\s*\S+', re.IGNORECASE), 'api_key…
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