การกรองข้อมูล

# Filter the days where the count of total_bill is greater than $40
total_bill_40 = restaurant_data.groupby('day').____(lambda x: ____[____].____() > 40)

# Print the number of tables where total_bill is greater than $40
print('Number of tables where total_bill is greater than $40:', total_bill_40.shape[0])