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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def paint_agent_trail(self, y, x, val):
 """ paint an agent trail as ONE pixel to allow for multiple agent trails to be seen in the same cell """

        for j in range(1,self.cell_height-1):
            for i in range(1,self.cell_width-1):
                self.img.put(self.agent_color(val), (x*self.cell_width+i, y*self.cell_height+j))