code: def get_world_dimensions(gridfile, delim=" "):
      
      infile = open(gridfile)
      lines = infile.readlines()
      infile.close()
      world_x = len(lines[0].strip().split(delim))
      world_y = len(lines)
      return (world_x, world_y)
docs: This function takes the name of a file in grid_task format and returns
      the dimensions of the world it represents.