Complete the Car class by creating an attribute purchase_price (type int) and the method print_info() that outputs the car's information. Ex: If the input is: 2011 18000 2018 where 2011 is the car's model year, 18000 is the purchase price, and 2018 is the current year, then print_info() outputs: Car's information: Model year: 2011 Purchase price: $18000 Current value: $5770 Note: print_info() should use two spaces for indentation.