find intersection among files

inter.py

import sys 

def parse(filename, limit):
  freqs = []
  with open(filename) as f:
    for l in f.readlines():
      l = l.strip().split()
      freqs.append((float(l[1]), l[0]))
  freqs.sort(reverse=True)
  if limit > len(freqs): limit = len(freqs)
  result = set([t[1] for t in freqs[:limit]])
  return result

if __name__ == '__main__':
  if (len(sys.argv) < 4): 
    print >>sys.stderr, "Usage: python inter.py limit filename1 filename2 ... "
  limit = int(sys.argv[1])
  setlist = [parse(filename, limit) for filename in sys.argv[2:]]
  final = setlist[0]
  for s in setlist[1:]:
    final.intersection_update(s)
  for word in final:
    print word