a simple battleship python script

I have written a simple python game script to sink a battleship. It is very simple as it was almost a year ago last time when I wrote a long python script. Thanks to codeacademy that it helps to brush up my python skills. I think it is also good to put the script here for my documentation. Simply, you guess the coordinates of the point and by default you have maximum 4 turns to do it right. Each time a guess is run, coordinate is marked by “X”. Below is a sample execution:

Here is the code itself:

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