old_contents: import subprocess
  
  p = subprocess.Popen('hdfs dfs -cat /user/roman/ngrams_merged/*', shell=True, stdout=subprocess.PIPE)
  
  VOCAB_FILE = open('1gms/vocab_cs', 'w')
  N_2_FILE = open('2gms/2gm-0001', 'w')
  N_3_FILE = open('3gms/2gm-0001', 'w')
  
  for line in p.stdout:
      line_len = len(line.split('\t')[0].split())
      if line_len == 1:
          VOCAB_FILE.write(line)
      elif line_len == 2:
          N_2_FILE.write(line)
      elif line_len == 3:
          N_3_FILE.write(line)
  
  VOCAB_FILE.close()
  N_2_FILE.close()
  N_3_FILE.close()
new_contents: import subprocess
  
  p = subprocess.Popen('hdfs dfs -cat /user/roman/ngrams_merged/*', shell=True, stdout=subprocess.PIPE)
  
  VOCAB_FILE = open('1gms/vocab_cs', 'w')
  N_2_FILE = open('2gms/2gm-0001', 'w')
  N_3_FILE = open('3gms/3gm-0001', 'w')
  
  for line in p.stdout:
      line_len = len(line.split('\t')[0].split())
      if line_len == 1:
          VOCAB_FILE.write(line)
      elif line_len == 2:
          N_2_FILE.write(line)
      elif line_len == 3:
          N_3_FILE.write(line)
  
  VOCAB_FILE.close()
  N_2_FILE.close()
  N_3_FILE.close()
subject: fix output