code: def width(self) -> int:
          
          max_x = -1.0
          for x, _ in self.entries.keys():
              max_x = max(max_x, x)
          for v in self.vertical_lines:
              max_x = max(max_x, v.x)
          for h in self.horizontal_lines:
              max_x = max(max_x, h.x1, h.x2)
          return 1 + int(max_x)
docs: Determines how many entry columns are in the diagram.