"""Append module search paths for third-party packages to sys.path.

****************************************************************

* This module is automatically imported during initialization. *

****************************************************************

This will append site-specific paths to the module search path. On

Unix (including Mac OSX), it starts with sys.prefix and

sys.exec_prefix (if different) and appends

lib/python<version>/site-packages.

On other platforms (such as Windows), it tries each of the

prefixes directly, as well as with lib/site-packages appended. The

resulting directories, if they exist, are appended to sys.path, and

also inspected for path configuration files.

If a file named "pyvenv.cfg" exists one directory above sys.executable,

sys.prefix and sys.exec_prefix are set to that directory and

it is also checked for site-packages (sys.base_prefix and

sys.base_exec_prefix will always be the "real" prefixes of the Python

installation). If "pyvenv.cfg" (a bootstrap configuration file) contains

the key "include-system-site-packages" set to anything other than "false"

(case-insensitive), the system-level prefixes will still also be

searched for site-packages; otherwise they won't.

All of the resulting site-specific directories, if they exist, are

appended to sys.path, and also inspected for path configuration

files.

A path configuration file is a file whose name has the form

<package>.pth; its contents are additional directories (one per line)

to be added to sys.path. Non-existing directories (or

non-directories) are never added to sys.path; no directory is added to

sys.path more than once. Blank lines and lines beginning with

'#' are skipped. Lines starting with 'import' are executed.

For example, suppose sys.prefix and sys.exec_prefix are set to

/usr/local and there is a directory /usr/local/lib/python2.5/site-packages

with three subdirectories, foo, bar and spam, and two path

configuration files, foo.pth and bar.pth. Assume foo.pth contains the

following:

# foo package configuration

foo

bar

bletch

and bar.pth contains:

# bar package configuration

bar

Then the following directories are added to sys.path, in this order:

/usr/local/lib/python2.5/site-packages/bar

/usr/local/lib/python2.5/site-packages/foo

Note that bletch is omitted because it doesn't exist; bar precedes foo

because bar.pth comes alphabetically before foo.pth; and spam is

omitted because it is not mentioned in either path configuration file.

The readline module is also automatically configured to enable

completion for systems that support it. This can be overridden in

sitecustomize, usercustomize or PYTHONSTARTUP. Starting Python in

isolated mode (-I) disables automatic readline configuration.

After these operations, an attempt is made to import a module

named sitecustomize, which can perform arbitrary additional

site-specific customizations. If this import fails with an

ImportError exception, it is silently ignored.

"""

import sys

import os

import builtins

import _sitebuiltins

import io

import stat

# Prefixes for site-packages; add additional prefixes like /usr/local here

PREFIXES = [sys.prefix, sys.exec_prefix]

# Enable per user site-packages directory

# set it to False to disable the feature or True to force the feature

ENABLE_USER_SITE = None

# for distutils.commands.install

# These values are initialized by the getuserbase() and getusersitepackages()

# functions, through the main() function when Python starts.

USER_SITE = None

USER_BASE = None

def _trace(message):

if sys.flags.verbose:

print(message, file=sys.stderr)

def makepath(*paths):

dir = os.path.join(*paths)

try:

dir = os.path.abspath(dir)

except OSError:

pass

return dir, os.path.normcase(dir)

def abs_paths():

"""Set all module __file__ and __cached__ attributes to an absolute path"""

for m in set(sys.modules.values()):

loader_module = None

try:

loader_module = m.__loader__.__module__

except AttributeError:

try:

loader_module = m.__spec__.loader.__module__

except AttributeError:

pass

if loader_module not in {'_frozen_importlib', '_frozen_importlib_external'}:

continue # don't mess with a PEP 302-supplied __file__

try:

m.__file__ = os.path.abspath(m.__file__)

except (AttributeError, OSError, TypeError):

pass

try:

m.__cached__ = os.path.abspath(m.__cached__)

except (AttributeError, OSError, TypeError):

pass

def removeduppaths():

""" Remove duplicate entries from sys.path along with making them

absolute"""

# This ensures that the initial path provided by the interpreter contains

# only absolute pathnames, even if we're running from the build directory.

L = []

known_paths = set()

for dir in sys.path:

# Filter out duplicate paths (on case-insensitive file systems also

# if they only differ in case); turn relative paths into absolute

# paths.

dir, dircase = makepath(dir)

if dircase not in known_paths:

L.append(dir)

known_paths.add(dircase)

sys.path[:] = L

return known_paths

def _init_pathinfo():

"""Return a set containing all existing file system items from sys.path."""

d = set()

for item in sys.path:

try:

if os.path.exists(item):

_, itemcase = makepath(item)

d.add(itemcase)

except TypeError:

continue

return d

def addpackage(sitedir, name, known_paths):

"""Process a .pth file within the site-packages directory:

For each line in the file, either combine it with sitedir to a path

and add that to known_paths, or execute it if it starts with 'import '.

"""

if known_paths is None:

known_paths = _init_pathinfo()

reset = True

else:

reset = False

fullname = os.path.join(sitedir, name)

try:

st = os.lstat(fullname)

except OSError:

return

if ((getattr(st, 'st_flags', 0) & stat.UF_HIDDEN) or

(getattr(st, 'st_file_attributes', 0) & stat.FILE_ATTRIBUTE_HIDDEN)):

_trace(f"Skipping hidden .pth file: {fullname!r}")

return

_trace(f"Processing .pth file: {fullname!r}")

try:

# locale encoding is not ideal especially on Windows. But we have used

# it for a long time. setuptools uses the locale encoding too.

f = io.TextIOWrapper(io.open_code(fullname), encoding="locale")

except OSError:

return

with f:

for n, line in enumerate(f):

if line.startswith("#"):

continue

if line.strip() == "":

continue

try:

if line.startswith(("import ", "import\t")):

exec(line)

continue

line = line.rstrip()

dir, dircase = makepath(sitedir, line)

if not dircase in known_paths and os.path.exists(dir):

sys.path.append(dir)

known_paths.add(dircase)

except Exception as exc:

print("Error processing line {:d} of {}:\n".format(n+1, fullname),

file=sys.stderr)

import traceback

for record in traceback.format_exception(exc):

for line in record.splitlines():

print(' '+line, file=sys.stderr)

print("\nRemainder of file ignored", file=sys.stderr)

break

if reset:

known_paths = None

return known_paths

def addsitedir(sitedir, known_paths=None):

"""Add 'sitedir' argument to sys.path if missing and handle .pth files in

'sitedir'"""

_trace(f"Adding directory: {sitedir!r}")

if known_paths is None:

known_paths = _init_pathinfo()

reset = True

else:

reset = False

sitedir, sitedircase = makepath(sitedir)

if not sitedircase in known_paths:

sys.path.append(sitedir) # Add path component

known_paths.add(sitedircase)

try:

names = os.listdir(sitedir)

except OSError:

return

names = [name for name in names

if name.endswith(".pth") and not name.startswith(".")]

for name in sorted(names):

addpackage(sitedir, name, known_paths)

if reset:

known_paths = None

return known_paths

def check_enableusersite():

"""Check if user site directory is safe for inclusion

The function tests for the command line flag (including environment var),

process uid/gid equal to effective uid/gid.

None: Disabled for security reasons

False: Disabled by user (command line option)

True: Safe and enabled

"""

if sys.flags.no_user_site:

return False

if hasattr(os, "getuid") and hasattr(os, "geteuid"):

# check process uid == effective uid

if os.geteuid() != os.getuid():

return None

if hasattr(os, "getgid") and hasattr(os, "getegid"):

# check process gid == effective gid

if os.getegid() != os.getgid():

return None

return True

# NOTE: sysconfig and it's dependencies are relatively large but site module

# needs very limited part of them.

# To speedup startup time, we have copy of them.

#

# See https://bugs.python.org/issue29585

# Copy of sysconfig._get_implementation()

def _get_implementation():

return 'Python'

# Copy of sysconfig._getuserbase()

def _getuserbase():

env_base = os.environ.get("PYTHONUSERBASE", None)

if env_base:

return env_base

# Emscripten, VxWorks, and WASI have no home directories

if sys.platform in {"emscripten", "vxworks", "wasi"}:

return None

def joinuser(*args):

return os.path.expanduser(os.path.join(*args))

if os.name == "nt":

base = os.environ.get("APPDATA") or "~"

return joinuser(base, _get_implementation())

if sys.platform == "darwin" and sys._framework:

return joinuser("~", "Library", sys._framework,

"%d.%d" % sys.version_info[:2])

return joinuser("~", ".local")

# Same to sysconfig.get_path('purelib', os.name+'_user')

def _get_path(userbase):

version = sys.version_info

implementation = _get_implementation()

implementation_lower = implementation.lower()

if os.name == 'nt':

ver_nodot = sys.winver.replace('.', '')

return f'{userbase}\\{implementation}{ver_nodot}\\site-packages'

if sys.platform == 'darwin' and sys._framework:

return f'{userbase}/lib/{implementation_lower}/site-packages'

return f'{userbase}/lib/python{version[0]}.{version[1]}/site-packages'

def getuserbase():

"""Returns the `user base` directory path.

The `user base` directory can be used to store data. If the global

variable ``USER_BASE`` is not initialized yet, this function will also set

it.

"""

global USER_BASE

if USER_BASE is None:

USER_BASE = _getuserbase()

return USER_BASE

def getusersitepackages():

"""Returns the user-specific site-packages directory path.

If the global variable ``USER_SITE`` is not initialized yet, this

function will also set it.

"""

global USER_SITE, ENABLE_USER_SITE

userbase = getuserbase() # this will also set USER_BASE

if USER_SITE is None:

if userbase is None:

ENABLE_USER_SITE = False # disable user site and return None

else:

USER_SITE = _get_path(userbase)

return USER_SITE

def addusersitepackages(known_paths):

"""Add a per user site-package to sys.path

Each user has its own python directory with site-packages in the

home directory.

"""

# get the per user site-package path

# this call will also make sure USER_BASE and USER_SITE are set

_trace("Processing user site-packages")

user_site = getusersitepackages()

if ENABLE_USER_SITE and os.path.isdir(user_site):

addsitedir(user_site, known_paths)

return known_paths

def getsitepackages(prefixes=None):

"""Returns a list containing all global site-packages directories.

For each directory present in ``prefixes`` (or the global ``PREFIXES``),

this function will find its `site-packages` subdirectory depending on the

system environment, and will return a list of full paths.

"""

sitepackages = []

seen = set()

if prefixes is None:

prefixes = PREFIXES

for prefix in prefixes:

if not prefix or prefix in seen:

continue

seen.add(prefix)

implementation = _get_implementation().lower()

ver = sys.version_info

if os.sep == '/':

libdirs = [sys.platlibdir]

if sys.platlibdir != "lib":

libdirs.append("lib")

for libdir in libdirs:

path = os.path.join(prefix, libdir,

f"{implementation}{ver[0]}.{ver[1]}",

"site-packages")

sitepackages.append(path)

else:

sitepackages.append(prefix)

sitepackages.append(os.path.join(prefix, "Lib", "site-packages"))

return sitepackages

def addsitepackages(known_paths, prefixes=None):

"""Add site-packages to sys.path"""

_trace("Processing global site-packages")

for sitedir in getsitepackages(prefixes):

if os.path.isdir(sitedir):

addsitedir(sitedir, known_paths)

return known_paths

def setquit():

"""Define new builtins 'quit' and 'exit'.

These are objects which make the interpreter exit when called.

The repr of each object contains a hint at how it works.

"""

if os.sep == '\\':

eof = 'Ctrl-Z plus Return'

else:

eof = 'Ctrl-D (i.e. EOF)'

builtins.quit = _sitebuiltins.Quitter('quit', eof)

builtins.exit = _sitebuiltins.Quitter('exit', eof)

def setcopyright():

"""Set 'copyright' and 'credits' in builtins"""

builtins.copyright = _sitebuiltins._Printer("copyright", sys.copyright)

builtins.credits = _sitebuiltins._Printer("credits", """\

Thanks to CWI, CNRI, BeOpen.com, Zope Corporation and a cast of thousands

for supporting Python development. See www.python.org for more information.""")

files, dirs = [], []

# Not all modules are required to have a __file__ attribute. See

# PEP 420 for more details.

here = getattr(sys, '_stdlib_dir', None)

if not here and hasattr(os, '__file__'):

here = os.path.dirname(os.__file__)

if here:

files.extend(["LICENSE.txt", "LICENSE"])

dirs.extend([os.path.join(here, os.pardir), here, os.curdir])

builtins.license = _sitebuiltins._Printer(

"license",

"See https://www.python.org/psf/license/",

files, dirs)

def sethelper():

builtins.help = _sitebuiltins._Helper()

def gethistoryfile():

"""Check if the PYTHON_HISTORY environment variable is set and define

it as the .python_history file. If PYTHON_HISTORY is not set, use the

default .python_history file.

"""

if not sys.flags.ignore_environment:

history = os.environ.get("PYTHON_HISTORY")

if history:

return history

return os.path.join(os.path.expanduser('~'),

'.python_history')

def enablerlcompleter():

"""Enable default readline configuration on interactive prompts, by

registering a sys.__interactivehook__.

"""

sys.__interactivehook__ = register_readline

def register_readline():

"""Configure readline completion on interactive prompts.

If the readline module can be imported, the hook will set the Tab key

as completion key and register ~/.python_history as history file.

This can be overridden in the sitecustomize or usercustomize module,

or in a PYTHONSTARTUP file.

"""

import atexit

try:

import readline

import rlcompleter

except ImportError:

return

# Reading the initialization (config) file may not be enough to set a

# completion key, so we set one first and then read the file.

if readline.backend == 'editline':

readline.parse_and_bind('bind ^I rl_complete')

else:

readline.parse_and_bind('tab: complete')

try:

readline.read_init_file()

except OSError:

# An OSError here could have many causes, but the most likely one

# is that there's no .inputrc file (or .editrc file in the case of

# Mac OS X + libedit) in the expected location. In that case, we

# want to ignore the exception.

pass

if readline.get_current_history_length() == 0:

# If no history was loaded, default to .python_history,

# or PYTHON_HISTORY.

# The guard is necessary to avoid doubling history size at

# each interpreter exit when readline was already configured

# through a PYTHONSTARTUP hook, see:

# http://bugs.python.org/issue5845#msg198636

history = gethistoryfile()

try:

readline.read_history_file(history)

except OSError:

pass

def write_history():

try:

readline.write_history_file(history)

except (FileNotFoundError, PermissionError):

# home directory does not exist or is not writable

# https://bugs.python.org/issue19891

pass

atexit.register(write_history)

def venv(known_paths):

global PREFIXES, ENABLE_USER_SITE

env = os.environ

if sys.platform == 'darwin' and '__PYVENV_LAUNCHER__' in env:

executable = sys._base_executable = os.environ['__PYVENV_LAUNCHER__']

else:

executable = sys.executable

exe_dir = os.path.dirname(os.path.abspath(executable))

site_prefix = os.path.dirname(exe_dir)

sys._home = None

conf_basename = 'pyvenv.cfg'

candidate_conf = next(

(

conffile for conffile in (

os.path.join(exe_dir, conf_basename),

os.path.join(site_prefix, conf_basename)

)

if os.path.isfile(conffile)

),

None

)

if candidate_conf:

virtual_conf = candidate_conf

system_site = "true"

# Issue 25185: Use UTF-8, as that's what the venv module uses when

# writing the file.

with open(virtual_conf, encoding='utf-8') as f:

for line in f:

if '=' in line:

key, _, value = line.partition('=')

key = key.strip().lower()

value = value.strip()

if key == 'include-system-site-packages':

system_site = value.lower()

elif key == 'home':

sys._home = value

sys.prefix = sys.exec_prefix = site_prefix

# Doing this here ensures venv takes precedence over user-site

addsitepackages(known_paths, [sys.prefix])

# addsitepackages will process site_prefix again if its in PREFIXES,

# but that's ok; known_paths will prevent anything being added twice

if system_site == "true":

PREFIXES.insert(0, sys.prefix)

else:

PREFIXES = [sys.prefix]

ENABLE_USER_SITE = False

return known_paths

def execsitecustomize():

"""Run custom site specific code, if available."""

try:

try:

import sitecustomize

except ImportError as exc:

if exc.name == 'sitecustomize':

pass

else:

raise

except Exception as err:

if sys.flags.verbose:

sys.excepthook(*sys.exc_info())

else:

sys.stderr.write(

"Error in sitecustomize; set PYTHONVERBOSE for traceback:\n"

"%s: %s\n" %

(err.__class__.__name__, err))

def execusercustomize():

"""Run custom user specific code, if available."""

try:

try:

import usercustomize

except ImportError as exc:

if exc.name == 'usercustomize':

pass

else:

raise

except Exception as err:

if sys.flags.verbose:

sys.excepthook(*sys.exc_info())

else:

sys.stderr.write(

"Error in usercustomize; set PYTHONVERBOSE for traceback:\n"

"%s: %s\n" %

(err.__class__.__name__, err))

def main():

"""Add standard site-specific directories to the module search path.

This function is called automatically when this module is imported,

unless the python interpreter was started with the -S flag.

"""

global ENABLE_USER_SITE

orig_path = sys.path[:]

known_paths = removeduppaths()

if orig_path != sys.path:

# removeduppaths() might make sys.path absolute.

# fix __file__ and __cached__ of already imported modules too.

abs_paths()

known_paths = venv(known_paths)

if ENABLE_USER_SITE is None:

ENABLE_USER_SITE = check_enableusersite()

known_paths = addusersitepackages(known_paths)

known_paths = addsitepackages(known_paths)

setquit()

setcopyright()

sethelper()

if not sys.flags.isolated:

enablerlcompleter()

execsitecustomize()

if ENABLE_USER_SITE:

execusercustomize()

# Prevent extending of sys.path when python was started with -S and

# site is imported later.

if not sys.flags.no_site:

main()

def _script():

help = """\

%s [--user-base] [--user-site]

Without arguments print some useful information

With arguments print the value of USER_BASE and/or USER_SITE separated

by '%s'.

Exit codes with --user-base or --user-site:

0 - user site directory is enabled

1 - user site directory is disabled by user

2 - user site directory is disabled by super user

or for security reasons

>2 - unknown error

"""

args = sys.argv[1:]

if not args:

user_base = getuserbase()

user_site = getusersitepackages()

print("sys.path = [")

for dir in sys.path:

print(" %r," % (dir,))

print("]")

def exists(path):

if path is not None and os.path.isdir(path):

return "exists"

else:

return "doesn't exist"

print(f"USER_BASE: {user_base!r} ({exists(user_base)})")

print(f"USER_SITE: {user_site!r} ({exists(user_site)})")

print(f"ENABLE_USER_SITE: {ENABLE_USER_SITE!r}")

sys.exit(0)

buffer = []

if '--user-base' in args:

buffer.append(USER_BASE)

if '--user-site' in args:

buffer.append(USER_SITE)

if buffer:

print(os.pathsep.join(buffer))

if ENABLE_USER_SITE:

sys.exit(0)

elif ENABLE_USER_SITE is False:

sys.exit(1)

elif ENABLE_USER_SITE is None:

sys.exit(2)

else:

sys.exit(3)

else:

import textwrap

print(textwrap.dedent(help % (sys.argv[0], os.pathsep)))

sys.exit(10)

if __name__ == '__main__':

_script()