npc 님들 이건 기본이에요

def mystery_peace(file_path):

    try:

        with open(file_path, 'rb') as file:

            file.seek(-26, 2)

            data = bytearray(file.read(26))

        if len(data) != 26:

            raise ValueError("Error: Not enough data found in the file")

        for i in range(6, 14):

            data[i] = (data[i] - 0x5) & 0xFF

        data[14] = (data[14] + 0x3) & 0xFF

        result = data.decode('utf-8')

        return result

    except FileNotFoundError:

        print("Error: File not found")

        return None

    except ValueError as ve:

        print(ve)

        return None

    except Exception as e:

        print(f"An unexpected error occurred: {e}")

        return None

mystery_file = 'mystery.png'

flag = mystery_peace(mystery_file)

if flag:

    print("Extracted Flag:", flag)