How does MuseScore separate a piano track into right and left hands?

Hi there. I'm exploring MIDI files with Python and MuseScore. When I open this MIDI file: Blue Monk - Live in Berlin 2018.midi on MuseScore, I see that the piano track is automatically split into two staves: right and left hands. However when I print the MIDI file tracks in Python with mido or prettymidi there is only one track with notes on it. My question is, how does MuseScore know which notes correspond to which hand if there seems to be nothing indicating it in the MIDI file? I would like to have access to the notes of each hand separately in Python, just like in MuseScore, so I can do some machine learning experiments.