StorageCraft ShadownProtect backup file (.spf)

def is_spf(file_path: str) -> bool:
    """Check if file is a valid SPF by magic bytes."""
    signature = bytes([0x53, 0x50, 0x46, 0x49, 0x00])
    with open(file_path, "rb") as f:
        return f.read(5) == signature

function isSPF(buffer: Buffer): boolean {
  const signature = Buffer.from([0x53, 0x50, 0x46, 0x49, 0x00]);
  return buffer.subarray(0, 5).equals(signature);
}

func IsSPF(data []byte) bool {
    signature := []byte{0x53, 0x50, 0x46, 0x49, 0x00}
    if len(data) < 5 {
        return false
    }
    return bytes.Equal(data[:5], signature)
}