code: def demo_TextGrid(demo_data):
      print("** Demo of the TextGrid class. **")
  
      fid = TextGrid(demo_data)
      print("Tiers: %s" % (fid.size))
  
      for i, tier in enumerate(fid):
          print("\n***")
          print("Tier: %s" % (i + 1))
          print(tier)
  
imports: import sys
  import re
label_desc: Use image node_id 1 for calling a global function with example usage: demo_TextGrid(demo_data) without return types