Music generated from the Fibonacci sequence and output to midi

fibonacci-midi.py

import midi

# Music generated from the Fibonacci sequence and output to midi
# Inspired by https://dev.to/daniel40392/visualizing-fibonacci-for-the-music-lover-in-you-2609
# Using https://github.com/vishnubob/python-midi for midi output
# Please excuse any python or music theory mistakes, I'm not an expert at either 

print('Welcome to the Fibonacci Composer.')
x = int(input('Enter Song Length: '))
k = input('Enter Song Key (C, G, D, A, E, B, F#, Db, Ab, Eb, Bb, F): ')
q = input('Enter Key Quality (maj, min): ')

keys = {
    'C': ["C","D","E","F","G","A","B"],
    'G': ["G","A","B","C","D","E","F#"],
    'D': ["D","E","F#","G","A","B","C#"],
    'A': ["A","B","C#","D","E","F#","G#"],
    'E': ["E","F#","G#","A","B","C#","D#"],
    'B': ["B","C#","D#","E","F#","G#","A#"],
    'F#': ["F#","G#","A#","B","C#","D#","E#"],
    'Db': ["Db","Eb","F","Gb","Ab","Bb","C"],
    'Ab': ["Ab","Bb","C","Db","Eb","F","G"],
    'Eb': ["Eb","F","G","Ab","Bb","C","D"],
    'Bb': ["Bb","C","D","Eb","F","G","A"],
    'F': ["F","G","A","Bb","C","D","E"]
}

relatives = {
    'A': 'C',
    'E': 'G',
    'B': 'D',
    'F#': 'A',
    'Db': 'E',
    'Ab': 'B',
    'Eb': 'F#',
    'Bb': 'Db',
    'F': 'Ab',
    'C': 'Eb',
    'G': 'Bb',
    'D': 'F'
}

pitches = {
    'C': midi.C_3,
    'G': midi.G_3,
    'D': midi.D_3,
    'A': midi.A_3,
    'E': midi.E_3,
    'B': midi.B_3,
    'F#': midi.Fs_3,
    'Gb': midi.Fs_3,
    'C#': midi.Cs_3,
    'Db': midi.Cs_3,
    'G#': midi.Gs_3,
    'Ab': midi.Gs_3,
    'D#': midi.Ds_3,
    'Eb': midi.Ds_3,
    'A#': midi.As_3,
    'Bb': midi.As_3,
    'E#': midi.F_3,
    'F': midi.F_3
}

key = keys[k] if q=='maj' else keys[relatives[k]]
song = []

def fib(n):
    """Function that generates notes based off the Fibonnachi Series"""
    a=0
    b=1
    print('Fibonacci in ' + str(k) + str(q) + ': ', end=' ')
    first = 0 if q=='maj' else 5
    song.append(key[first])
    for i in range (1,n):
        fib=a+b
        mod = fib%7 - 1 if fib%7 - 1 >=0 else 6
        mod = mod if q=='maj' else (mod+5)%7
        song.append(key[mod])
        a=b
        b=fib
    for i in song:
        print (i + ', ', end='')
    print('\n')
    to_midi(song, 'fibonacci-' + str(k) + str(q) + '.mid')

def to_midi(song, filename):
    pattern = midi.Pattern()
    track = midi.Track()
    pattern.append(track)
    for i in song:
        on = midi.NoteOnEvent(tick=0, velocity=60, pitch=pitches[i])
        track.append(on)
        off = midi.NoteOffEvent(tick=100, pitch=pitches[i])
        track.append(off)
    eot = midi.EndOfTrackEvent(tick=1)
    track.append(eot)
    midi.write_midifile(filename, pattern)
    
while x != '':
    fib(x)
    print()
    quit()