old_contents: import os
  import subprocess
  import os.path
  
  def apt_get_install(fname):
      with open(fname, 'r') as f:
          items = f.readlines()
      for item in items:
          os.system('sudo apt-get install -y %s' % (item))
  
  def npm_global_install(fname):
      with open(fname, 'r') as f:
          items = f.readlines()
      for item in items:
          os.system('sudo npm -g install %s' % (item))
  
  def pip_install(fname):
      with open(fname, 'r') as f:
          items = f.readlines()
      for item in items:
          os.system('sudo pip install %s' % (item))
  
  def cmd_exists(cmd):
      # this is from http://stackoverflow.com/questions/377017/test-if-executable-exists-in-python
      return subprocess.call("type " + cmd, shell=True, 
          stdout=subprocess.PIPE, stderr=subprocess.PIPE) == 0
  
  functions_to_handle_requirements = {}
  functions_to_handle_requirements['apt_get'] = apt_get_install
  functions_to_handle_requirements['npm'] = npm_global_install
  functions_to_handle_requirements['pip'] = pip_install
  print functions_to_handle_requirements['npm']
  order_of_files_to_handle = ['apt_get_requirements.txt', 'npm_requirements.txt', 'pip_requirements.txt']
  
  for fname in order_of_files_to_handle:
      if os.path.isfile(fname):
          # assume fname endswith _requirements.txt
          l = len('_requirements.txt')
          fname_first_part = fname[:-l]
          functions_to_handle_requirements[fname_first_part](fname)
new_contents: import os
  import subprocess
  import os.path
  
  def apt_get_install(fname):
      with open(fname, 'r') as f:
          items = f.readlines()
      for item in items:
          os.system('sudo apt-get install -y %s' % (item))
  
  def npm_global_install(fname):
      with open(fname, 'r') as f:
          items = f.readlines()
      for item in items:
          os.system('sudo npm -g install %s' % (item))
  
  def pip_install(fname):
      with open(fname, 'r') as f:
          items = f.readlines()
      for item in items:
          os.system('sudo pip install %s' % (item))
  
  def cmd_exists(cmd):
      # this is from http://stackoverflow.com/questions/377017/test-if-executable-exists-in-python
      return subprocess.call("type " + cmd, shell=True, 
          stdout=subprocess.PIPE, stderr=subprocess.PIPE) == 0
  
  functions_to_handle_requirements = {}
  functions_to_handle_requirements['apt_get'] = apt_get_install
  functions_to_handle_requirements['npm'] = npm_global_install
  functions_to_handle_requirements['pip'] = pip_install
  print 'DEBUG DEBUG DEBUG npm function', functions_to_handle_requirements['npm']
  order_of_files_to_handle = ['apt_get_requirements.txt', 'npm_requirements.txt', 'pip_requirements.txt']
  
  for fname in order_of_files_to_handle:
      if os.path.isfile(fname):
          # assume fname endswith _requirements.txt
          l = len('_requirements.txt')
          fname_first_part = fname[:-l]
          functions_to_handle_requirements[fname_first_part](fname)
subject: add debugging