Can someone please explain me the draw_map function?I have difficulties trying to understand the way it is written.

Hey, I have found it easier to understand if you actually take each cell in CELLS, and start drawing on a piece of paper as defined by the code.

CELLS = [(0,0), (1,0), (2,0), (3,0), (4,0),

                (0,1), (1,1), (2,1), (3,1), (4,1),

                (0,2), (1,2), (2,2), (3,2), (4,2),

                (0,3), (1,3), (2,3), (3,3), (4,3),

                (0,4), (1,4), (2,4), (3,4), (4,4)] 

player = (0,1)

You start by drawing 5 x " _" which gives you the upper end of the map. So you have a single line composed of 5 small _. It looks like this:

 _ _ _ _ _

The first item is (0,0). So we are in the case where x < 4 (0 < 4), and (0,0) is different from (0,1) (player). The code reads:

• line_end ="" that means after this first item is printed, the next item will stay on the same line (as opposed to a line break)
• output = tile.format("_") meaning what you draw for position (0,0) is a |_ . Your map should resemble:

 _ _ _ _ _
|_

The next item is (1,0), so again 1 < 4 and (1,0) different from (2,3). If you apply the same logic, your map should resemble:

 _ _ _ _ _
|_|_

... same for (2,0), (3,0) ...

Let's look at when you reach the last item with y =0. For (4,0), we are in the case where x > 4, and (4,0) is not (0,1). The code reads:

• line_end = "\" that means after this we go to the next line instead of continuing horizontally.
• output = tile.format("_|") this is to close the right hand side of the map, otherwise it would be open like |_ instead of |_|

Now your map should resemble:

 _ _ _ _ _
|_|_|_|_|_|

When we reach the player at (0,1), we are in the case where 0 <4, so:

• line-end =""
• output = tile.format("X") (that's basically |X) Note as in Kenneth' video, there is no line under the X.

Your map would resemble:

 _ _ _ _ _
|_|_|_|_|_|
|X

So on for the rest of the tuples in CELLS.

Hope you understand the logic better now. It is always a good thing to start drawing the map by hand, and back engineer how you would execute it in code.

And I Would like to add to this awesome explanation that after line_end='\n':

there's also an if-else statement which means IF your player is located on the 4th x draw a tile.format(X|) which looks like this |X|.

this explanation really helped