code: def create_bootstrap_script(extra_text, python_version=''):
      
      filename = __file__
      if filename.endswith('.pyc'):
          filename = filename[:-1]
      f = codecs.open(filename, 'r', encoding='utf-8')
      content = f.read()
      f.close()
      py_exe = 'python%s' % python_version
      content = (('#!/usr/bin/env %s\n' % py_exe)
                 + '## WARNING: This file is generated\n'
                 + content)
      return content.replace('##EXT' 'END##', extra_text)
docs: Creates a bootstrap script, which is like this script but with
      extend_parser, adjust_options, and after_install hooks.
  
      This returns a string that (written to disk of course) can be used
      as a bootstrap script with your own customizations.  The script
      will be the standard virtualenv.py script, with your extra text
      added (your extra text should be Python code).
  
      If you include these functions, they will be called:
  
      ``extend_parser(optparse_parser)``:
          You can add or remove options from the parser here.
  
      ``adjust_options(options, args)``:
          You can change options here, or change the args (if you accept
          different kinds of arguments, be sure you modify ``args`` so it is
          only ``[DEST_DIR]``).
  
      ``after_install(options, home_dir)``:
  
          After everything is installed, this function is called.  This
          is probably the function you are most likely to use.  An
          example would be::
  
              def after_install(options, home_dir):
                  subprocess.call([join(home_dir, 'bin', 'easy_install'),
                                   'MyPackage'])
                  subprocess.call([join(home_dir, 'bin', 'my-package-script'),
                                   'setup', home_dir])
  
          This example immediately installs a package, and runs a setup
          script from that package.
  
      If you provide something like ``python_version='2.5'`` then the
      script will start with ``#!/usr/bin/env python2.5`` instead of
      ``#!/usr/bin/env python``.  You can use this when the script must
      be run with a particular Python version.