2FA Backup Code Generator

import secrets
import string

def generate_backup_code(length: int = 8) -> str:
    """Generate a single 2FA backup code in XXXX-XXXX format."""
    alphabet = string.ascii_uppercase + string.digits
    # Remove ambiguous characters
    alphabet = alphabet.replace('O', '').replace('0', '').replace('I', '').replace('1', '')
    code = ''.join(secrets.choice(alphabet) for _ in range(length))
    return f"{code[:4]}-{code[4:]}"

def generate_backup_codes(count: int = 10) -> list[str]:
    """Generate a set of unique 2FA backup codes."""
    codes = set()
    while len(codes) < count:
        codes.add(generate_backup_code())
    return sorted(codes)

# Generate 10 backup codes
codes = generate_backup_codes(10)
for i, code in enumerate(codes, 1):
    print(f"{i:2}. {code}")