tuples are called rgb values notice the spacing of the tuples on lines to are such that the rgand integers line up in python the indentation (that isthe space at the beginning of the lineis needs to be exactbut the spacing in the rest of the line is not so strict by spacing the integers in the tuple outwe can clearly see how the rgb values compare to each other (more info on spacing and indentation is as it is nice thing to make your code more readable this waybut don' bother spending too much time doing it code doesn' have to be pretty to work at certain pointyou'll just be spending more time typing spaces than you would have saved by having readable tuple values using constant variables instead of strings donut 'donut square 'square diamond 'diamond lines 'lines oval 'ovalthe program also sets up constant variables for some strings these constants will be used in the data structure for the boardtracking which spaces on the board have which icons using constant variable instead of the string value is good idea look at the following codewhich comes from line if shape =donutthe shape variable will be set to one of the strings 'donut''square''diamond''lines'or 'ovaland then compared to the donut constant if we made typo when writing line for examplesomething like thisif shape =dunotthen python would crashgiving an error message saying that there is no variable named dunot this is good since the program has crashed on line when we check that line it will be easy to see that the bug was caused by typo howeverif we were using strings instead of constant variables and made the same typoline would look like thisif shape ='dunot'this is perfectly acceptable python codeso it won' crash at first when you run it howeverthis will lead to weird bugs later on in our program because the code does not immediately crash where the problem is causedit can be much harder to find it email questions to the authoral@inventwithpython com