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Masking

Replace detected PII with asterisks while preserving the original value length.

PrivacyGuard.mask() replaces each detected value with asterisks.

Basic masking

from fastpii import PrivacyGuard

guard = PrivacyGuard(regions=["cz"])
text = "Kontakt: jan.novak@email.cz, RČ 8001011238, IČO 25596641"

masked = guard.mask(text)
print(masked)

Output:

Kontakt: ******************, RČ **********, IČO ********

Preserves original length

The mask length matches len(finding.value) for each detected item.

from fastpii import PrivacyGuard

guard = PrivacyGuard(regions=["cz"])

print(guard.mask("Email: jan.novak@email.cz"))
print(guard.mask("IČO: 25596641"))

Possible output:

Email: ******************
IČO: ********

Use masking when you want to hide the value but keep rough layout and length cues.

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