When it comes to paying bills at restaurants, Wallace always leaves a 15% tip based on the pretax price. However, Wallace is tired of computing tips every time, please construct a function total_bill, which takes a numerical argument pretax and returns the total bill by 1) calculating the tip, 2) the after-tax price, and 3) adding the tip to the after-tax price. Assume the sale tax is 9%. Below is how the function would be used: pretax = 15
print('The total bill is ${}'.format(total_bill(pretax)))
The output should be:
The total bill is $18.6