Тропарь пред̾ иконой Пресвѧтыѧ Богородицы «Оумиле́нїе»

Unable to compile LilyPond input file:

Processing `.../file.ly'
Parsing...
.../file.ly:3:1: error: syntax error, unexpected \set

\set midiInstrument = #"flute"
Interpreting music...[8][8]
Preprocessing graphical objects...
Interpreting music...
MIDI output to `file.midi'...
Finding the ideal number of pages...
Fitting music on 1 page...
Drawing systems...
Layout output to `file.ps'...
Converting to PNG...
fatal error: failed files: ".../file.ly"

exited with status: 1