Count scopes defined in Textmate color themes, than sort them and print

tmks.py

#!/usr/bin/env python3
# -*- coding: utf-8 -*-

import os
import operator

try:
  from collections import defaultdict
except Exception:
  print("Failed to import defaultdict")
  
try:
  from lxml import etree
except ImportError:
  try:
    # Python 2.5
    import xml.etree.cElementTree as etree
    print("running with cElementTree on Python 2.5+")
  except ImportError:
    try:
      # Python 2.5
      import xml.etree.ElementTree as etree
      print("running with ElementTree on Python 2.5+")
    except ImportError:
      try:
        # normal cElementTree install
        import cElementTree as etree
        print("running with cElementTree")
      except ImportError:
        try:
          # normal ElementTree install
          import elementtree.ElementTree as etree
          print("running with ElementTree")
        except ImportError:
          print("Failed to import ElementTree from any known place")

themes_path = "./TextMate-Themes/"
textmate_extension = ".tmTheme"
occurrences = defaultdict(int)
filenames = []

# get filenames of Textmate themes
for oDirPaths, oDirNames, oFiles in os.walk(themes_path, True, None):
  filenames.append(oFiles)

filenames = filenames[0]

# remove all not Textmate themes
for filename in filenames:
  if (not filename.endswith(textmate_extension)):
    filenames.remove(filename)

# check each Textmate theme for list of declared scopes
for filename in filenames:
  
  try:
    tree = etree.parse(themes_path + filename)
    
    strings = tree.findall(".//string")
    
    for element in strings: 
      if ("scope" == str(element.getprevious().text)):
        for scope in str(element.text).split(","):
          occurrences[scope.strip()] += 1
          
  except Exception:
    print("INVALID: " + filename)

sorted_occurrences = sorted(occurrences.items(), key=lambda x: x[0])
sorted_occurrences = sorted(sorted_occurrences, key=lambda x: x[1], reverse=True)

print("\noccurrences\tscopes\n")

for entry in sorted_occurrences:
  print("\t" + str(entry[1]) + ":\t" + entry[0])
  
print("\n" + str(len(sorted_occurrences)) + " scopes in " + str(len(filenames)) + " Textmate themes.\n")