Correlate .mat files with songs in Nottingham dataset

[demongolem-biz2]

I have all the .abc files. I have made sure the shape of all the X variables combined is the same as the number of songs. But after I load the .mat file for Nottingham how do I say that the first element in the numpy array corresponds to the song entitled "...."? I want to match data with songs listed in the .abc files.