wf.py

import re; import sys
from collections import defaultdict

try:
  file = open(sys.argv[1])
except:
  print "Usage: python wf.py <path_to_file/filename>"

word_freq = defaultdict(int) 
for line in file:
  words = re.findall('\w+', line.strip())
  for word in words:
    word_freq[word.lower()] += 1

for word, freq in sorted(word_freq.iteritems()):
  print word, freq