Update Metadata of MP3 File in C#

using (var metadata = new GroupDocs.Metadata.Metadata("input.mp3"))
{
	// set the value of each property that satisfies the predicate:
	// property contains the date/time the document was created
	// update the file creation date/time if the existing value is older than 3 days
	var affected = metadata.UpdateProperties(
		p => p.Tags.Contains(GroupDocs.Metadata.Tagging.Tags.Time.Created) &&
		p.Value.Type == GroupDocs.Metadata.Common.MetadataPropertyType.DateTime &&
		p.Value.ToStruct() < DateTime.Today.AddDays(-3), new GroupDocs.Metadata.Common.PropertyValue(DateTime.Today));
	Console.WriteLine("Properties set: {0}", affected);
	metadata.Save("output.mp3");
}