old_contents: #!/usr/bin/python3
  
  import os
  import json
  import glob
  
  data = {}
  data['comparisonfiles'] = {}
  
  for subset in next(os.walk("comparisonfiles/"))[1]:
      data['comparisonfiles'][subset] = {}
      data['comparisonfiles'][subset]["format"] = []
      format_list = [
          format
          for format in next(os.walk("comparisonfiles/" + subset + "/large"))[1]
      ]
      for format in format_list:
          extension = [
              os.path.splitext(os.path.basename(fn))[1][1:]
              for fn in glob.glob(
                  "comparisonfiles/" + subset + "/large/" + format + "/*")
              if os.path.splitext(os.path.basename(fn))[1] != "png"
          ][0]
          data['comparisonfiles'][subset]["format"].append({
              "extension": extension,
              "name": format
          })
  
      data['comparisonfiles'][subset]["format"].append({
          "extension": "png",
          "name": "Original"
      })
  
      filenames_list = [
          os.path.splitext(os.path.basename(files))[0]
          for files in next(
              os.walk("comparisonfiles/" + subset + "/Original/"))[2]
      ]
      data['comparisonfiles'][subset]["files"] = []
      for filename in filenames_list:
          data['comparisonfiles'][subset]["files"].append({
              "title": "",
              "filename": filename
          })
  
  with open('comparisonfiles.json', 'w') as outfile:
      json.dump(data, outfile, indent=4)
  
new_contents: #!/usr/bin/python3
  
  import os
  import json
  import glob
  
  data = {}
  data['comparisonfiles'] = {}
  
  for subset in next(os.walk("comparisonfiles/"))[1]:
      data['comparisonfiles'][subset] = {}
      data['comparisonfiles'][subset]["format"] = []
      format_list = [
          format
          for format in next(os.walk("comparisonfiles/" + subset + "/large"))[1]
      ]
      for format in format_list:
          extension = [
              os.path.splitext(os.path.basename(fn))[1][1:]
              for fn in glob.glob(
                  "comparisonfiles/" + subset + "/large/" + format + "/*")
              if os.path.splitext(os.path.basename(fn))[1] != ".png"
          ][0]
          data['comparisonfiles'][subset]["format"].append({
              "extension": extension,
              "name": format
          })
  
      data['comparisonfiles'][subset]["format"].append({
          "extension": "png",
          "name": "Original"
      })
  
      filenames_list = [
          os.path.splitext(os.path.basename(files))[0]
          for files in next(
              os.walk("comparisonfiles/" + subset + "/Original/"))[2]
      ]
      data['comparisonfiles'][subset]["files"] = []
      for filename in filenames_list:
          data['comparisonfiles'][subset]["files"].append({
              "title": "",
              "filename": filename
          })
  
  with open('comparisonfiles.json', 'w') as outfile:
      json.dump(data, outfile, indent=4)
  
subject: Fix extension detection in JSON generation