example.py

class Grid():
    def __init__(self, rows, cols, fill = 0): 
        self.rows = rows
        self.cols = cols 
        self.fill = fill
        self.grid = self.make_grid(self.rows, self.cols, self.fill)
    def make_grid(self, rows, cols, fill):
        #return [[self.fill for col in range(self.cols)] for row in range(self.rows)]
        local = []
        for row in range(self.rows):
            local.append([])
        for row in range(self.rows):
            for col in range(self.cols):
                local[row].append(self.fill)
        return local
    def display(self):
        for row in self.grid:
            print(row)
        
def main():
    main_grid = Grid.make_grid(3,3,Grid(10,10)) #makes a 3x3 grid filled with 10x10 Grid objects
    print(main_grid[4][5].grid[2][4])
if __name__ == "__main__":
    main()