Masking Sensitive Information with Regex

Using regular expressions to mask credit card numbers in text

Python
import re

def mask_credit_card(text):
    pattern = r'\b(?:\d{4}[-\s]?){3}\d{4}\b'
    return re.sub(pattern, lambda m: '*' * 12 + m.group()[-4:], text)

sample_text = "Credit card: 1234-5678-9012-3456 and 9876543210123456"
masked_text = mask_credit_card(sample_text)
print("Original:", sample_text)
print("Masked:", masked_text)