fetch_aud_ftrs.py

def fetch_audio_features(sp, username, playlist_id):
    """
    Returns the selected audio features of every track, 
    for the given playlist.
    """
    
    # Use the fetch_playlist_tracks function to fetch all of the tracks
    playlist = fetch_playlist_tracks(sp, username, playlist_id)
    index = 0
    audio_features = []
    
    # Make the API request
    while index < playlist.shape[0]:
        audio_features += sp.audio_features(playlist.iloc[index:index + 50, 0])
        index += 50
    
    # Append the audio features in a list
    features_list = []
    for features in audio_features:
        features_list.append([features['danceability'],
                              features['energy'], features['tempo'],
                              features['loudness'], features['valence']])
    
    df_audio_features = pd.DataFrame(features_list, columns=['danceability', 'energy',
                                                             'tempo', 'loudness', 'valence'])

    # Set the 'tempo' & 'loudness' in the same range with the rest features
    for feature in df_audio_features.columns:
        if feature == 'tempo' or feature == 'loudness':
            continue
        df_audio_features[feature] = df_audio_features[feature] * 100
    
    # Create the final df, using the 'track_id' as index for future reference
    df_playlist_audio_features = pd.concat([playlist, df_audio_features], axis=1)
    df_playlist_audio_features.set_index('track_id', inplace=True, drop=True)
    
    return df_playlist_audio_features