how to verify downloaded file?

hello again,
here is my code that I use to download a file:

```
using (var response = await client.Files.DownloadAsync(file.AsFile.PathDisplay))
{
File.WriteAllBytes(folder + "/" + realName, await response.GetContentAsByteArrayAsync());
}
```

but my question is: how can I check if the downloaded file is correct? is there a checksum or md5 or someother thing?

thanks in advance