#find the highest selling brand
autos['brand'].value_counts(normalize=True)[:10]

# find the price ranges within brands
brands_mean_price = {}
for brand in autos['brand'].unique():
    if brand not in brands_mean_price:
        brands_mean_price[brand] = round(autos['price_dollar'][autos['brand']==brand].mean(), 0)
# Sort dictionary by values in reverse order
sorted(((value, key) for (key,value) in brands_mean_price.items()), reverse=True)[:20]