Side note: If you find this spectrogram confusing, it may be due to your familiarity with the convention of placing low frequencies 
at the bottom and high frequencies at the top of a plot. However, when plotting spectrograms as an image using the matplotlib library, 
the y-axis is flipped and the spectrograms appear upside down.
Now apply the processing function to the entire dataset. This will take between 5 and 10 minutes.

dataset = dataset.map(prepare_dataset, remove_columns=dataset.column_names)