Always protect sensitive data through proper encryption, secure cookies, and careful exception handling to prevent information leakage.

When handling sensitive data:

1. Use secure cookie attributes - Always set Secure and HttpOnly flags for cookies containing sensitive information:

   response.set_cookie(
    settings.CSRF_COOKIE_NAME,
    request.META.get("CSRF_COOKIE"),
    secure=True,
    httponly=True,
    samesite='Lax',
    domain=settings.CSRF_COOKIE_DOMAIN,
   )
   

2. Encrypt sensitive credentials - Use proper cryptographic methods for storing or transmitting API keys, tokens, and other secrets: ```python

   Generate cryptographically secure key

   key = Fernet.generate_key() # Returns base64 encoded key ready for use

Use Fernet for encryption

fernet = Fernet(key) encrypted_token = fernet.encrypt(token.encode(“utf-8”))

3. **Prevent information leakage in exceptions** - Avoid exposing stack traces or internal details to users:
```python
# Don't do this:
raise ParseError(detail=str(e))  # May leak sensitive information

# Instead, use controlled error messages:
raise ParseError(detail="Invalid or missing date range")

These practices help protect your application from various security vulnerabilities including session hijacking, credential exposure, and information disclosure.