text: """
  Virtual environment (venv) package for Python. Based on PEP 405.
  
  Copyright (C) 2011-2014 Vinay Sajip.
  Licensed to the PSF under a contributor agreement.
  """
  import logging
  import os
  import shutil
  import subprocess
  import sys
  import sysconfig
  import types
  
  
  CORE_VENV_DEPS = ('pip', 'setuptools')
  logger = logging.getLogger(__name__)
  
  
  class EnvBuilder:
      """
      This class exists to allow virtual environment creation to be
      customized. The constructor parameters determine the builder's
      behaviour when called upon to create a virtual environment.
  
      By default, the builder makes the system (global) site-packages dir
      *un*available to the created environment.
  
      If invoked using the Python -m option, the default is to use copying
      on Windows platforms but symlinks elsewhere. If instantiated some
      other way, the default is to *not* use symlinks.
  
      :param system_site_packages: If True, the system (global) site-packages
                                   dir is available to created environments.
      :param clear: If True, delete the contents of the environment directory if
                    it already exists, before environment creation.
      :param symlinks: If True, attempt to symlink rather than copy files into
                       virtual environment.
      :param upgrade: If True, upgrade an existing virtual environment.
      :param with_pip: If True, ensure pip is installed in the virtual
                       environment
      :param prompt: Alternative terminal prefix for the environment.
      :param upgrade_deps: Update the base venv modules to the latest on PyPI
      """
  
      def __init__(self, system_site_packages=False, clear=False,
                   symlinks=False, upgrade=False, with_pip=False, prompt=None,
                   upgrade_deps=False):
          self.system_site_packages = system_site_packages
          self.clear = clear
          self.symlinks = symlinks
          self.upgrade = upgrade
          self.with_pip = with_pip
          if prompt == '.':  # see bpo-38901
              prompt = os.path.basename(os.getcwd())
          self.prompt = prompt
          self.upgrade_deps = upgrade_deps
  
      def create(self, env_dir):
          """
          Create a virtual environment in a directory.
  
          :param env_dir: The target directory to create an environment in.
  
          """
          env_dir = os.path.abspath(env_dir)
          context = self.ensure_directories(env_dir)
          # See issue 24875. We need system_site_packages to be False
          # until after pip is installed.
          true_system_site_packages = self.system_site_packages
          self.system_site_packages = False
          self.create_configuration(context)
          self.setup_python(context)
          if self.with_pip:
              self._setup_pip(context)
          if not self.upgrade:
              self.setup_scripts(context)
              self.post_setup(context)
          if true_system_site_packages:
              # We had set it to False before, now
              # restore it and rewrite the configuration
              self.system_site_packages = True
              self.create_configuration(context)
          if self.upgrade_deps:
              self.upgrade_dependencies(context)
  
      def clear_directory(self, path):
          for fn in os.listdir(path):
              fn = os.path.join(path, fn)
              if os.path.islink(fn) or os.path.isfile(fn):
                  os.remove(fn)
              elif os.path.isdir(fn):
                  shutil.rmtree(fn)
  
      def ensure_directories(self, env_dir):
          """
          Create the directories for the environment.
  
          Returns a context object which holds paths in the environment,
          for use by subsequent logic.
          """
  
          def create_if_needed(d):
              if not os.path.exists(d):
                  os.makedirs(d)
              elif os.path.islink(d) or os.path.isfile(d):
                  raise ValueError('Unable to create directory %r' % d)
  
          if os.path.exists(env_dir) and self.clear:
              self.clear_directory(env_dir)
          context = types.SimpleNamespace()
          context.env_dir = env_dir
          context.env_name = os.path.split(env_dir)[1]
          prompt = self.prompt if self.prompt is not None else context.env_name
          context.prompt = '(%s) ' % prompt
          create_if_needed(env_dir)
          executable = sys._base_executable
          dirname, exename = os.path.split(os.path.abspath(executable))
          context.executable = executable
          context.python_dir = dirname
          context.python_exe = exename
          if sys.platform == 'win32':
              binname = 'Scripts'
              incpath = 'Include'
              libpath = os.path.join(env_dir, 'Lib', 'site-packages')
          else:
              binname = 'bin'
              incpath = 'include'
              libpath = os.path.join(env_dir, 'lib',
                                     'python%d.%d' % sys.version_info[:2],
                                     'site-packages')
          context.inc_path = path = os.path.join(env_dir, incpath)
          create_if_needed(path)
          create_if_needed(libpath)
          # Issue 21197: create lib64 as a symlink to lib on 64-bit non-OS X POSIX
          if ((sys.maxsize > 2**32) and (os.name == 'posix') and
              (sys.platform != 'darwin')):
              link_path = os.path.join(env_dir, 'lib64')
              if not os.path.exists(link_path):   # Issue #21643
                  os.symlink('lib', link_path)
          context.bin_path = binpath = os.path.join(env_dir, binname)
          context.bin_name = binname
          context.env_exe = os.path.join(binpath, exename)
          create_if_needed(binpath)
          # Assign and update the command to use when launching the newly created
          # environment, in case it isn't simply the executable script (e.g. bpo-45337)
          context.env_exec_cmd = context.env_exe
          if sys.platform == 'win32':
              # bpo-45337: Fix up env_exec_cmd to account for file system redirections.
              # Some redirects only apply to CreateFile and not CreateProcess
              real_env_exe = os.path.realpath(context.env_exe)
              if os.path.normcase(real_env_exe) != os.path.normcase(context.env_exe):
                  logger.warning('Actual environment location may have moved due to '
                                 'redirects, links or junctions.\n'
                                 '  Requested location: "%s"\n'
                                 '  Actual location:    "%s"',
                                 context.env_exe, real_env_exe)
                  context.env_exec_cmd = real_env_exe
          return context
  
      def create_configuration(self, context):
          """
          Create a configuration file indicating where the environment's Python
          was copied from, and whether the system site-packages should be made
          available in the environment.
  
          :param context: The information for the environment creation request
                          being processed.
          """
          context.cfg_path = path = os.path.join(context.env_dir, 'pyvenv.cfg')
          with open(path, 'w', encoding='utf-8') as f:
              f.write('home = %s\n' % context.python_dir)
              if self.system_site_packages:
                  incl = 'true'
              else:
                  incl = 'false'
              f.write('include-system-site-packages = %s\n' % incl)
              f.write('version = %d.%d.%d\n' % sys.version_info[:3])
              if self.prompt is not None:
                  f.write(f'prompt = {self.prompt!r}\n')
  
      if os.name != 'nt':
          def symlink_or_copy(self, src, dst, relative_symlinks_ok=False):
              """
              Try symlinking a file, and if that fails, fall back to copying.
              """
              force_copy = not self.symlinks
              if not force_copy:
                  try:
                      if not os.path.islink(dst): # can't link to itself!
                          if relative_symlinks_ok:
                              assert os.path.dirname(src) == os.path.dirname(dst)
                              os.symlink(os.path.basename(src), dst)
                          else:
                              os.symlink(src, dst)
                  except Exception:   # may need to use a more specific exception
                      logger.warning('Unable to symlink %r to %r', src, dst)
                      force_copy = True
              if force_copy:
                  shutil.copyfile(src, dst)
      else:
          def symlink_or_copy(self, src, dst, relative_symlinks_ok=False):
              """
              Try symlinking a file, and if that fails, fall back to copying.
              """
              bad_src = os.path.lexists(src) and not os.path.exists(src)
              if self.symlinks and not bad_src and not os.path.islink(dst):
                  try:
                      if relative_symlinks_ok:
                          assert os.path.dirname(src) == os.path.dirname(dst)
                          os.symlink(os.path.basename(src), dst)
                      else:
                          os.symlink(src, dst)
                      return
                  except Exception:   # may need to use a more specific exception
                      logger.warning('Unable to symlink %r to %r', src, dst)
  
              # On Windows, we rewrite symlinks to our base python.exe into
              # copies of venvlauncher.exe
              basename, ext = os.path.splitext(os.path.basename(src))
              srcfn = os.path.join(os.path.dirname(__file__),
                                   "scripts",
                                   "nt",
                                   basename + ext)
              # Builds or venv's from builds need to remap source file
              # locations, as we do not put them into Lib/venv/scripts
              if sysconfig.is_python_build(True) or not os.path.isfile(srcfn):
                  if basename.endswith('_d'):
                      ext = '_d' + ext
                      basename = basename[:-2]
                  if basename == 'python':
                      basename = 'venvlauncher'
                  elif basename == 'pythonw':
                      basename = 'venvwlauncher'
                  src = os.path.join(os.path.dirname(src), basename + ext)
              else:
                  src = srcfn
              if not os.path.exists(src):
                  if not bad_src:
                      logger.warning('Unable to copy %r', src)
                  return
  
              shutil.copyfile(src, dst)
  
      def setup_python(self, context):
          """
          Set up a Python executable in the environment.
  
          :param context: The information for the environment creation request
                          being processed.
          """
          binpath = context.bin_path
          path = context.env_exe
          copier = self.symlink_or_copy
          dirname = context.python_dir
          if os.name != 'nt':
              copier(context.executable, path)
              if not os.path.islink(path):
                  os.chmod(path, 0o755)
              for suffix in ('python', 'python3', f'python3.{sys.version_info[1]}'):
                  path = os.path.join(binpath, suffix)
                  if not os.path.exists(path):
                      # Issue 18807: make copies if
                      # symlinks are not wanted
                      copier(context.env_exe, path, relative_symlinks_ok=True)
                      if not os.path.islink(path):
                          os.chmod(path, 0o755)
          else:
              if self.symlinks:
                  # For symlinking, we need a complete copy of the root directory
                  # If symlinks fail, you'll get unnecessary copies of files, but
                  # we assume that if you've opted into symlinks on Windows then
                  # you know what you're doing.
                  suffixes = [
                      f for f in os.listdir(dirname) if
                      os.path.normcase(os.path.splitext(f)[1]) in ('.exe', '.dll')
                  ]
                  if sysconfig.is_python_build(True):
                      suffixes = [
                          f for f in suffixes if
                          os.path.normcase(f).startswith(('python', 'vcruntime'))
                      ]
              else:
                  suffixes = ['python.exe', 'python_d.exe', 'pythonw.exe',
                              'pythonw_d.exe']
  
              for suffix in suffixes:
                  src = os.path.join(dirname, suffix)
                  if os.path.lexists(src):
                      copier(src, os.path.join(binpath, suffix))
  
              if sysconfig.is_python_build(True):
                  # copy init.tcl
                  for root, dirs, files in os.walk(context.python_dir):
                      if 'init.tcl' in files:
                          tcldir = os.path.basename(root)
                          tcldir = os.path.join(context.env_dir, 'Lib', tcldir)
                          if not os.path.exists(tcldir):
                              os.makedirs(tcldir)
                          src = os.path.join(root, 'init.tcl')
                          dst = os.path.join(tcldir, 'init.tcl')
                          shutil.copyfile(src, dst)
                          break
  
      def _setup_pip(self, context):
          """Installs or upgrades pip in a virtual environment"""
          # We run ensurepip in isolated mode to avoid side effects from
          # environment vars, the current directory and anything else
          # intended for the global Python environment
          cmd = [context.env_exec_cmd, '-Im', 'ensurepip', '--upgrade',
                                                           '--default-pip']
          subprocess.check_output(cmd, stderr=subprocess.STDOUT)
  
      def setup_scripts(self, context):
          """
          Set up scripts into the created environment from a directory.
  
          This method installs the default scripts into the environment
          being created. You can prevent the default installation by overriding
          this method if you really need to, or if you need to specify
          a different location for the scripts to install. By default, the
          'scripts' directory in the venv package is used as the source of
          scripts to install.
          """
          path = os.path.abspath(os.path.dirname(__file__))
          path = os.path.join(path, 'scripts')
          self.install_scripts(context, path)
  
      def post_setup(self, context):
          """
          Hook for post-setup modification of the venv. Subclasses may install
          additional packages or scripts here, add activation shell scripts, etc.
  
          :param context: The information for the environment creation request
                          being processed.
          """
          pass
  
      def replace_variables(self, text, context):
          """
          Replace variable placeholders in script text with context-specific
          variables.
  
          Return the text passed in , but with variables replaced.
  
          :param text: The text in which to replace placeholder variables.
          :param context: The information for the environment creation request
                          being processed.
          """
          text = text.replace('__VENV_DIR__', context.env_dir)
          text = text.replace('__VENV_NAME__', context.env_name)
          text = text.replace('__VENV_PROMPT__', context.prompt)
          text = text.replace('__VENV_BIN_NAME__', context.bin_name)
          text = text.replace('__VENV_PYTHON__', context.env_exe)
          return text
  
      def install_scripts(self, context, path):
          """
          Install scripts into the created environment from a directory.
  
          :param context: The information for the environment creation request
                          being processed.
          :param path:    Absolute pathname of a directory containing script.
                          Scripts in the 'common' subdirectory of this directory,
                          and those in the directory named for the platform
                          being run on, are installed in the created environment.
                          Placeholder variables are replaced with environment-
                          specific values.
          """
          binpath = context.bin_path
          plen = len(path)
          for root, dirs, files in os.walk(path):
              if root == path: # at top-level, remove irrelevant dirs
                  for d in dirs[:]:
                      if d not in ('common', os.name):
                          dirs.remove(d)
                  continue # ignore files in top level
              for f in files:
                  if (os.name == 'nt' and f.startswith('python')
                          and f.endswith(('.exe', '.pdb'))):
                      continue
                  srcfile = os.path.join(root, f)
                  suffix = root[plen:].split(os.sep)[2:]
                  if not suffix:
                      dstdir = binpath
                  else:
                      dstdir = os.path.join(binpath, *suffix)
                  if not os.path.exists(dstdir):
                      os.makedirs(dstdir)
                  dstfile = os.path.join(dstdir, f)
                  with open(srcfile, 'rb') as f:
                      data = f.read()
                  if not srcfile.endswith(('.exe', '.pdb')):
                      try:
                          data = data.decode('utf-8')
                          data = self.replace_variables(data, context)
                          data = data.encode('utf-8')
                      except UnicodeError as e:
                          data = None
                          logger.warning('unable to copy script %r, '
                                         'may be binary: %s', srcfile, e)
                  if data is not None:
                      with open(dstfile, 'wb') as f:
                          f.write(data)
                      shutil.copymode(srcfile, dstfile)
  
      def upgrade_dependencies(self, context):
          logger.debug(
              f'Upgrading {CORE_VENV_DEPS} packages in {context.bin_path}'
          )
          cmd = [context.env_exec_cmd, '-m', 'pip', 'install', '--upgrade']
          cmd.extend(CORE_VENV_DEPS)
          subprocess.check_call(cmd)
  
  
  def create(env_dir, system_site_packages=False, clear=False,
             symlinks=False, with_pip=False, prompt=None, upgrade_deps=False):
      """Create a virtual environment in a directory."""
      builder = EnvBuilder(system_site_packages=system_site_packages,
                           clear=clear, symlinks=symlinks, with_pip=with_pip,
                           prompt=prompt, upgrade_deps=upgrade_deps)
      builder.create(env_dir)
  
  def main(args=None):
      compatible = True
      if sys.version_info < (3, 3):
          compatible = False
      elif not hasattr(sys, 'base_prefix'):
          compatible = False
      if not compatible:
          raise ValueError('This script is only for use with Python >= 3.3')
      else:
          import argparse
  
          parser = argparse.ArgumentParser(prog=__name__,
                                           description='Creates virtual Python '
                                                       'environments in one or '
                                                       'more target '
                                                       'directories.',
                                           epilog='Once an environment has been '
                                                  'created, you may wish to '
                                                  'activate it, e.g. by '
                                                  'sourcing an activate script '
                                                  'in its bin directory.')
          parser.add_argument('dirs', metavar='ENV_DIR', nargs='+',
                              help='A directory to create the environment in.')
          parser.add_argument('--system-site-packages', default=False,
                              action='store_true', dest='system_site',
                              help='Give the virtual environment access to the '
                                   'system site-packages dir.')
          if os.name == 'nt':
              use_symlinks = False
          else:
              use_symlinks = True
          group = parser.add_mutually_exclusive_group()
          group.add_argument('--symlinks', default=use_symlinks,
                             action='store_true', dest='symlinks',
                             help='Try to use symlinks rather than copies, '
                                  'when symlinks are not the default for '
                                  'the platform.')
          group.add_argument('--copies', default=not use_symlinks,
                             action='store_false', dest='symlinks',
                             help='Try to use copies rather than symlinks, '
                                  'even when symlinks are the default for '
                                  'the platform.')
          parser.add_argument('--clear', default=False, action='store_true',
                              dest='clear', help='Delete the contents of the '
                                                 'environment directory if it '
                                                 'already exists, before '
                                                 'environment creation.')
          parser.add_argument('--upgrade', default=False, action='store_true',
                              dest='upgrade', help='Upgrade the environment '
                                                 'directory to use this version '
                                                 'of Python, assuming Python '
                                                 'has been upgraded in-place.')
          parser.add_argument('--without-pip', dest='with_pip',
                              default=True, action='store_false',
                              help='Skips installing or upgrading pip in the '
                                   'virtual environment (pip is bootstrapped '
                                   'by default)')
          parser.add_argument('--prompt',
                              help='Provides an alternative prompt prefix for '
                                   'this environment.')
          parser.add_argument('--upgrade-deps', default=False, action='store_true',
                              dest='upgrade_deps',
                              help='Upgrade core dependencies: {} to the latest '
                                   'version in PyPI'.format(
                                   ' '.join(CORE_VENV_DEPS)))
          options = parser.parse_args(args)
          if options.upgrade and options.clear:
              raise ValueError('you cannot supply --upgrade and --clear together.')
          builder = EnvBuilder(system_site_packages=options.system_site,
                               clear=options.clear,
                               symlinks=options.symlinks,
                               upgrade=options.upgrade,
                               with_pip=options.with_pip,
                               prompt=options.prompt,
                               upgrade_deps=options.upgrade_deps)
          for d in options.dirs:
              builder.create(d)
  
  if __name__ == '__main__':
      rc = 1
      try:
          main()
          rc = 0
      except Exception as e:
          print('Error: %s' % e, file=sys.stderr)
      sys.exit(rc)
  