def download_missing_images(self, variables):

artists_cover = variables.dirs.artists_cover

artist_thumbnail = variables.dirs.artist_thumbnail

albums_thumbnail = variables.dirs.albums_thumbnail

downloader = [pics.get_band_cover, pics.get_band_thumbnail, pics.get_album_thumbnail]

iterable_list = [(Band, artists_cover), (Band, artist_thumbnail), (Album, albums_thumbnail)]

for index, (model, directory) in enumerate(iterable_list):

# Find all model ids which are already downloaded

model_ids_with_image = [img.strip('.jpg') for img in os.listdir(directory)]

# Find the contra model set for the above list

models_without_image = variables.session().query(model).filter\

(~model.id.in_(model_ids_with_image)).all()

for model in models_without_image:

if model.__class__ is Band:

variables.add_band(model.name, False, model.id)

variables.add_album(None, False, None)

elif model.__class__ is Album:

# Both album, band variables are required to download album related images

variables.add_band(model.band_name, False, model.band_id)

variables.add_album(model.name, False, model.id)

downloader[index](variables)

def __init__(self, arguments):

# Configure Session class with desired options

Session = sessionmaker()

# Import credentials

db_name = credentials.get_db_name()

db_user_name = credentials.get_db_user_name()

db_host = credentials.get_db_host()

db_password = credentials.get_db_password()

db_backend = credentials.get_db_backend()

# Later, we create the engine

engine = create_engine('{backend}://{user}:{password}@{host}/{name}?charset=utf8'

.format(backend=db_backend,

user=db_user_name,

password=db_password,

host=db_host,

name=db_name),

# echo=True

)

# Associate it with our custom Session class

Session.configure(bind=engine)

# API Credentials

API_KEY = credentials.get_lastfm_api_key()

API_SECRET = credentials.get_lastfm_api_secret()

DB_NAME = credentials.get_db_name()

network = pylast.LastFMNetwork(api_key=API_KEY,

api_secret=API_SECRET,)

variables = Variables(arguments, Session, network)