code: def get_line_height_stats(self):
      heights = [
          l.bbox[3] - l.bbox[1] for l in self.get_nonblank_lines()
      ]
      height_counts = Counter(heights)
      return height_counts
  
imports: from collections import Counter
  from typing import List, Optional, Tuple
  from pydantic import BaseModel, field_validator
  import ftfy
  from marker.bbox import boxes_intersect_pct, multiple_boxes_intersect
  from marker.settings import settings
label_desc: Use image node_id 6 for calling the Page obj's underlying member method code with example usage: obj.get_line_height_stats() and returns: height_counts