new_contents:  # ############################################################################
   #
   # Copyright (c) Microsoft Corporation. 
   #
   # This source code is subject to terms and conditions of the Apache License, Version 2.0. A 
   # copy of the license can be found in the License.html file at the root of this distribution. If 
   # you cannot locate the Apache License, Version 2.0, please send an email to 
   # vspython@microsoft.com. By using this source code in any fashion, you are agreeing to be bound 
   # by the terms of the Apache License, Version 2.0.
   #
   # You must not remove this notice, or any other, from this software.
   #
   # ###########################################################################
  
  import datetime
  import os
  import sys
  import traceback
  
  if sys.version_info[0] == 3:
      def to_str(value):
          return value.decode(sys.getfilesystemencoding())
  
      def execfile(path, global_dict):
          """Execute a file"""
          with open(path, 'r') as f:
              code = f.read()
          code = code.replace('\r\n', '\n') + '\n'
          exec(code, global_dict)
  else:
      def to_str(value):
          return value.encode(sys.getfilesystemencoding())
  
  def log(txt):
      """Logs fatal errors to a log file if WSGI_LOG env var is defined"""
      log_file = os.environ.get('WSGI_LOG')
      if log_file:
          f = open(log_file, 'a+')
          try:
              f.write('%s: %s' % (datetime.datetime.now(), txt))
          finally:
              f.close()
  
  ptvsd_secret = os.getenv('WSGI_PTVSD_SECRET')
  if ptvsd_secret:
      log('Enabling ptvsd ...\n')
      try:
          import ptvsd
          try:
              ptvsd.enable_attach(ptvsd_secret)
              log('ptvsd enabled.\n')
          except: 
              log('ptvsd.enable_attach failed\n')
      except ImportError:
          log('error importing ptvsd.\n')
  
  def get_wsgi_handler(handler_name):
      if not handler_name:
          raise Exception('WSGI_ALT_VIRTUALENV_HANDLER env var must be set')
      
      if not isinstance(handler_name, str):
          handler_name = to_str(handler_name)
      
      module_name, _, callable_name = handler_name.rpartition('.')
      should_call = callable_name.endswith('()')
      callable_name = callable_name[:-2] if should_call else callable_name
      name_list = [(callable_name, should_call)]
      handler = None
      last_tb = ''
  
      while module_name:
          try:
              handler = __import__(module_name, fromlist=[name_list[0][0]])
              last_tb = ''
              for name, should_call in name_list:
                  handler = getattr(handler, name)
                  if should_call:
                      handler = handler()
              break
          except ImportError:
              module_name, _, callable_name = module_name.rpartition('.')
              should_call = callable_name.endswith('()')
              callable_name = callable_name[:-2] if should_call else callable_name
              name_list.insert(0, (callable_name, should_call))
              handler = None
              last_tb = ': ' + traceback.format_exc()
      
      if handler is None:
          raise ValueError('"%s" could not be imported%s' % (handler_name, last_tb))
      
      return handler
  
  activate_this = os.getenv('WSGI_ALT_VIRTUALENV_ACTIVATE_THIS')
  if not activate_this:
      raise Exception('WSGI_ALT_VIRTUALENV_ACTIVATE_THIS is not set')
  
  def get_virtualenv_handler():
      log('Activating virtualenv with %s\n' % activate_this)
      execfile(activate_this, dict(__file__=activate_this))
  
      log('Getting handler %s\n' % os.getenv('WSGI_ALT_VIRTUALENV_HANDLER'))
      handler = get_wsgi_handler(os.getenv('WSGI_ALT_VIRTUALENV_HANDLER'))
      log('Got handler: %r\n' % handler)
      return handler
  
  def get_venv_handler():
      log('Activating venv with executable at %s\n' % activate_this)
      import site
      sys.executable = activate_this
      old_sys_path, sys.path = sys.path, []
      
      site.main()
      
      sys.path.insert(0, '')
      for item in old_sys_path:
          if item not in sys.path:
              sys.path.append(item)
  
      log('Getting handler %s\n' % os.getenv('WSGI_ALT_VIRTUALENV_HANDLER'))
      handler = get_wsgi_handler(os.getenv('WSGI_ALT_VIRTUALENV_HANDLER'))
      log('Got handler: %r\n' % handler)
      return handler
  
subject: Create ptvs_virtualenv_proxy.py