Full boar with prompting and searching

script.py

def findTopSong(sp, artist, allTargetSongs):
    allTopTracks = sp.artist_top_tracks(artist['id'] , country='US')['tracks']
    if len(allTopTracks) <= 3: return
    singleTopTrack = allTopTracks[0] # Grabs top Track
    allTargetSongs.append(singleTopTrack)

# Takes sp for auth, the current artist being looked at, the current threshold for popularity
# and how far removed (linkLevel) the current artist is from the original favorite artists. 
# Ultimately the goal of this function is to take someone's top 10 favorite artists and return 
# underground artists with on especially popular song relative to the average of their top 5 songs. 

def findUnpopularRelated(sp, artist, popThresh, linkLevel, allTargetSongs):
    relatedArtists = sp.artist_related_artists(artist['id'])
    if len(relatedArtists) < 1: return
    if len(relatedArtists['artists']) < 1: return
    artist = relatedArtists['artists'][0]
    for artist in relatedArtists['artists']:
        if artist['popularity'] < popThresh and popThresh >= 30: 
            findTopSong(sp, artist, allTargetSongs)    
            findUnpopularRelated(sp, artist, popThresh - 10, linkLevel + 1, allTargetSongs)

def promptForArtists(sp):
    searchedArtists = []
    nextArtist = None
    while True:
        nextArtist = input("Please enter an artist's name: ")
        if nextArtist == "": return searchedArtists
        result = sp.search(nextArtist, limit=10, offset=0, type='artist', market=None)['artists']['items'][0]
        searchedArtists.append(result)


if __name__ == '__main__':
    username = "<Your username>"
    token = util.prompt_for_user_token(username,scope = 'user-top-read',client_id='<Your id>',client_secret='<Your secret>',redirect_uri='http://localhost/')
    if token:
        sp = spotipy.Spotify(auth=token)
        allTargetSongs = []
        startingArtists = promptForArtists(sp)
        for artist in startingArtists:
            print("Looking at artist: " + artist['name'])
            findUnpopularRelated(sp, artist, 60, 1, allTargetSongs)
        printFoundSongs(allTargetSongs)