我如何使用x, y坐标矩阵来选择一个字符出现在字符串中的python?

I am attempting to make a simple maze game to test a NNS with genetic algorithms. the maze for each test would use a matrix to hold the x, y points of things like barriers, the start, the end, and the player's current position. The main thing that I need help with is placing the right character in the right location in a string so when the strings of row 1-25 are read (probably with a for loop) it will read out a layout of the map. As an example, the barrier points 1,1 3,4 and 1,5 would look like this if an "o" is a space: first stringI am attempting to make a simple maze game to t