check

def get_artists(df):
    """
    Get artist information (artist_name, artist_msid etc) for every user
    ordered by listen count (number of times a user has listened to tracks
    which belong to a particular artist).

    Args:
        table: name of the temporary table.

    Returns:
        artists: A dict of dicts which can be depicted as:
                {
                    'user1': [{
                        'artist_name': str,
                        'artist_msid': str,
                        'artist_mbids': str,
                        'listen_count': int
                    }],
                    'user2' : [{...}]
                }
    """
    t0 = time.time()
    df = df.select("user_name", "artist_name", "artist_msid", "artist_mbids")
	df = df.groupBy("user_name", "artist_name", "artist_msid", "artist_mbids").count()
	df = df.sort(df['count'].desc())
	results = df.collect()
	artists = defaultdict(list)
	for row in rows:
	  artists[row.user_name].append({
	    'artist_name': row.artist_name,
	    'artist_msid': row.artist_msid,
	    'artist_mbid': row.artist_mbids,
	    'listen_count': row['count']
	  })
    print("Query to calculate artist stats processed in %.2f s" % (time.time() - t0))
    return artists